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| United States Patent |
5,720,895
|
|
Nakagawa
, et al.
|
February 24, 1998
|
Polyol ether derivatives and production methods therefor
Abstract
Polyol ether derivatives, a method for producing the polyol ether
derivatives, and a working fluid composition for a refrigerating machine
containing a hydrofluorocarbon and a refrigeration oil containing the
polyol ether derivatives as a base oil.
| Inventors:
|
Nakagawa; Shoji (Wakayama, JP);
Sawada; Hiroki (Wakayama, JP);
Togashi; Hiroyasu (Wakayama, JP);
Hagihara; Toshiya (Wakayama, JP)
|
| Assignee:
|
Kao Corporation (Tokyo, JP)
|
| Appl. No.:
|
512651 |
| Filed:
|
August 8, 1995 |
Foreign Application Priority Data
| Current U.S. Class: |
252/68; 252/67; 508/307 |
| Intern'l Class: |
C09K 005/04; C10M 105/18 |
| Field of Search: |
252/68,67
508/307
|
References Cited
U.S. Patent Documents
| 3741986 | Jun., 1973 | Hartmann | 549/372.
|
| 5523010 | Jun., 1996 | Sorensen et al. | 508/307.
|
| 5575944 | Nov., 1996 | Sawada et al. | 252/68.
|
| Foreign Patent Documents |
| 0019999 | Oct., 1980 | EP.
| |
| 0092998 | Feb., 1983 | EP.
| |
| 0460614 | Dec., 1991 | EP.
| |
| 0624563 | Nov., 1994 | EP.
| |
| 2303815 | Mar., 1976 | FR.
| |
| 4124199 | Jan., 1993 | DE.
| |
| 5-98275 | Apr., 1993 | JP.
| |
| 6-57243 | Jan., 1994 | JP.
| |
| 2100256 | Dec., 1982 | GB.
| |
| 93 24435 | Dec., 1993 | WO.
| |
| 9606839 | Mar., 1996 | WO.
| |
Primary Examiner: Skane; Christine
Attorney, Agent or Firm: Birch, Stewart, Kolasch & Birch, LLP
Claims
What is claimed is:
1. A working fluid composition for a refrigerating machine, comprising a
hydrofluorocarbon and a refrigeration oil containing as a base oil a
polyol ether derivative represented by the following formula (XIII.sub.AA)
or (XIII.sub.BB):
##STR48##
wherein R.sup.1 to R.sup.6 may be identical or different, each
representing a linear alkyl group having 1-14 carbon atoms, a branched
alkyl group having 3-14 carbon atoms or a cyclic alkyl group having 3-14
carbon atoms; R.sup.7 represents an hydrogen atom, or a linear alkyl group
having 1-13 carbon atoms, a branched alkyl group having 3-13 carbon atoms
or a cyclic alkyl group having 3-13 carbon atoms; R.sup.8 represents a
linear alkyl group having 1-13 carbon atoms, a branched alkyl group having
3-13 carbon atoms or a cyclic alkyl group having 3-13 carbon atoms;
R.sup.7 and R.sup.8 may together join to form a ring with an alkylene
group having 2-13 carbon atoms; the total number of carbon atoms is 8-40
for R.sup.1, R.sup.2, R.sup.3, R.sup.6, R.sup.7 and R.sup.8 in formula
(XIII.sub.AA), and for R.sup.1, R.sup.4, R.sup.5, R.sup.6, R.sup.7 and
R.sup.8 in formula (XIII.sub.BB), and is 1-13 for R.sup.7 and R.sup.8 in
formulas (XIII.sub.AA and XIII.sub.BB); and the specific structures within
the parenthesis may be arranged in any sequential order.
2. The working fluid composition for a refrigerating machine according to
claim 1, wherein a hexahydric alcohol residue of the compound represented
by formula (XIII.sub.AA) or (XIII.sub.BB) is derived from sorbitol.
3. The working fluid composition for a refrigerating machine according to
claim 1 or 2, wherein the compound represented by formula (XIII.sub.AA) or
(XIII.sub.BB) is synthesized by the steps of:
reacting a hexahydric alcohol represented by the following formula (V):
##STR49##
with (a) one or more carbonyl compounds represented by the following
formula (XII) for ketalization or acetalization:
##STR50##
wherein R.sup.7 represents a hydrogen atom, a linear alkyl group having
1-13 carbon atoms, a branched alkyl group having 3-13 carbon atoms or a
cyclic alkyl group having 3-13 carbon atoms, and R.sup.8 represents a
linear alkyl group having 1-13 carbon atoms, a branched alkyl group having
3-13 carbon atoms, or a cyclic alkyl group having 3-13 carbon atoms with
the proviso that R.sup.7 and/or R.sup.8 have at least one hydrogen atom at
.alpha.-position to the carbonyl group, and the total number of carbon
atoms of R.sup.7 and R.sup.8 is 1-13; and R.sup.7 and R.sup.8 may together
join to form a ring with an alkylene group having 2-13 carbon atoms; or
with (b) reactive derivatives of said carbonyl compounds thereof for
transketalization or transacetalization to obtain a cyclic ketal or a
cyclic acetal;
hydrogenating the cyclic ketal or the cyclic acetal to obtain a polyol
ether ketal or a polyol ether acetal; and
alkylating the polyol ether ketal or the polyol ether acetal.
4. The working fluid composition for a refrigerating machine according to
claim 1 or 2, which further comprises one or more compounds selected from
the group consisting of (a) 0.05 to 2.0 parts by weight of an epoxy
compound, (b) 0.01 to 100 parts by weight of an orthoester compound, (c)
0.01 to 100 parts by weight of an acetal or a ketal, and (d) 0.05 to 5
parts by weight of carbodiimide, each amount of (a) to (d) being based on
100 parts by weight of the polyol ether derivative represented by formula
(XIII.sub.AA) or (XIII.sub.BB).
5. The working fluid composition for a refrigerating machine according to
claim 3, which further comprises one or more compounds selected from the
group consisting of (a) 0.05 to 2.0 parts by weight of an epoxy compound,
(b) 0.01 to 100 parts by weight of an orthoester compound, (c) 0.01 to 100
parts by weight of an acetal or a ketal, and (d) 0.05 to 5 parts by weight
of carbodiimide, each amount of (a) to (d) being based on 100 parts by
weight of the polyol ether derivative represented by formula (XIII.sub.AA)
or (XIII.sub.BB).
6. The working fluid composition for a refrigerating machine according to
claim 1, wherein said polyol ether derivative has an average molecular
weight in the range of from 200 to 800.
7. The working fluid composition for a refrigerating machine according to
claim 1, wherein said polyol ether derivative has an average molecular
weight in the range of from 300 to 700.
8. The working fluid composition for a refrigerating machine according to
claim 1, wherein said polyol ether derivative has a viscosity at
100.degree. C. of from 0.5 to 30 mm.sup.2 /s.
9. The working fluid composition for a refrigerating machine according to
claim 1, wherein said polyol ether derivative has a viscosity at
40.degree. C. of from 1 to 300 mm.sup.2 /s.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to polyol ether derivatives which are useful
as polar oils, organic solvents, lubricants, synthetic lubricating oils,
or refrigeration oils, or as intermediates in the production of the above
oils, etc.; and to a method for producing the polyol ether derivatives;
and also to a working fluid composition for a refrigerating machine using
the above polyol ether derivatives as a base oil. Here, the term "polyol
ether" means a partially etherified polyol.
2. Discussion of the Related Art
Recently, the use of dichlorodifluoromethane (CFC12) for refrigerators and
car air conditioners has been restricted, and will be legally banned in
order to protect the ozone layer. Also, the use of chlorodifluoromethane
(HCFC22) for room air conditioners is about to be legally regulated. Thus,
hydrofluorocarbons which do not destroy the ozone layer, such as
1,1,1,2-tetrafluoroethane (HFC 134a), difluoromethane (HFC32), and
pentafluoroethane (HFC125), have been developed as substitutes for CFC12
or HCFC22.
However, since the polarity of hydrofluorocarbons is higher than that of
CFC12 or HCFC22, the use of conventional lubricating oils, such as
naphthenic mineral oils, poly-.alpha.-olefins, or alkylbenzenes, causes
two-layer separation of the working fluid at low temperatures. This is due
to poor compatibility between the conventional lubricating oils and
hydrofluorocarbons. Two-layer separation hampers oil return, which in turn
interferes with heat transfer due to deposition of a thick oil film on a
heat transfer surface of the condenser and evaporator used as heat
exchangers. It can also cause significant failures, such as poor
lubrication, and foaming upon starting operation. Therefore, the
conventional refrigeration oils cannot be used as refrigeration oils under
these new refrigerant atmospheres.
As for lubricity, CFC12 and HCFC22 generate hydrogen chloride upon partial
decomposition. The hydrogen chloride thus formed reacts with the friction
surface to form a coating of chlorides, thereby improving the lubricity.
On the other hand, non chlorine containing hydrofluorocarbons are not
expected to have such an effect; therefore, refrigeration oils used in
combination with hydrofluorocarbons are required to have a further
excellent lubricity when compared to the conventional refrigeration oils.
In addition, the refrigeration oils used in combination with
hydrofluorocarbons have to have good thermal stability in the presence of
hydrofluorocarbons.
Moreover, with compression-type refrigerating machines for electric
refrigerators and air conditioners, since organic materials are used for
motor components, such as insulators and enameled wires, the working fluid
comprising a hydrofluorocarbon and a refrigeration oil is required to have
no adverse effects on these organic materials and also have a good
insulating property.
Refrigeration oils which can be used in combination with
hydrofluorocarbons, such as 1,1,1,2-tetrafluoroethane (HFC134a), disclosed
in U.S. Pat. No. 4,755,316 and Japanese Patent Laid-Open No. 2-129294, are
ether compounds of polyalkylene glycols (hereinafter abbreviated as
PAG-OH) prepared by the addition of an alkylene oxide to a polyhydric
alcohol which is not alkyl-capped at the terminal hydroxyl. As an example
of the polyhydric alcohols used, the former discloses trimethylol propane
and the latter discloses glycerol.
In order to solve various problems of the above compounds, such as poor
compatibility with HFC and high hygroscopicity, compounds prepared by
alkyl-capping the terminal hydroxyl groups of the above ether compounds
(hereinafter abbreviated as PAG) are disclosed in Japanese Patent
Laid-Open Nos. 3-14894, 3-205492, 4-20596, 4-359996, and 5-98275.
Since PAG-OH and PAG have a higher polarity than the naphthenic mineral
oils, their compatibility with HFC134a at low temperatures is good.
However, PAG-OH and PAG phase-separate as the temperature increases as
mentioned in U.S. Pat. No. 4,755,316. There are also several problems with
these compounds. For example, a poor insulating property is one of the
problems. Due to this significant problem, PAG-OH and PAG cannot be used
for a refrigerating device of electric refrigerators and air conditioners
where a motor is incorporated in a compressor. Therefore, applications of
PAG-OH and PAG are proposed for car air conditioners where their poor
insulating property does not cause any problems. High hygroscopicity is
another significant problem of PAG-OH and PAG. The water absorbed by the
compounds causes thermal instability of the compounds in the presence of
HFC134a, and hydrolysis of organic materials, such as PET films.
In order to solve the above problems of polyether compounds, such as poor
insulating property and high hygroscopicity, ester compounds and carbonate
compounds have been developed. For example, mixed oils of polyether oils
and ester oils are disclosed in U.S. Pat. No. 4,851,144 (corresponding to
Japanese Patent Laid-Open No. 2-276894) and Japanese Patent Laid-Open No.
2-158693; ester oils are disclosed in Japanese Patent Laid-Open Nos.
3-505602, 3-128991, and 3-128992; and carbonate oils are disclosed in
Japanese Patent Laid-Open Nos. 2-132178 and 3-149295, and European Patent
No. 421,298. All of the compounds disclosed can be used as a refrigeration
oil in combination with 1,1,1,2-tetrafluoroethane (HFC134a).
Ester compounds and carbonate compounds show good compatibility with
hydrofluorocarbons and high thermal stability in the presence of
hydrofluorocarbons. Also, these compounds have markedly better insulating
properties and much lower hygroscopicity than polyether compounds.
However, when compared with the conventional CFC12-mineral oil working
fluid system, both freon and oil tend to have a high polarity in the
hydrofluorocarbon-ester oil system or hydrofluorocarbon-carbonate oil
system, and the systems become highly hygroscopic. Particularly, in the
system using an ester oil, a carboxylic acid is likely to be formed owing
to hydrolysis of the ester oil, and the formed carboxylic acid may in turn
corrode and wear down the metals. Also, in the case of using a carbonate
oil, there arises such a problem that a non-condensable carbon dioxide gas
is generated owing to hydrolysis of the carbonate oil to cause a low
refrigerating capacity.
In particular, in the case of room air conditioners, it is common practice
to fill an air conditioner with a refrigerant upon installation.
Therefore, unlike refrigerating machines for which filling of refrigerant
is carried out in a factory, it is almost impossible to prevent a working
fluid of room air conditioners from being contaminated with water.
Therefore, there has been a concern about the reliability of the
hydrofluorocarbon-ester oil system and hydrofluorocarbon-carbonate oil
system, when used in room air conditioners.
W093/24435 discloses that a polyvinyl ether compound having good
compatibility with hydrofluorocarbons and good insulating property is
prepared by polymerization of vinyl ether monomers and subsequent
hydrogenation. However, since the polyvinyl ether compound is synthesized
by polymerization, it shows molecular weight distribution. Therefore, a
part of high molecular weight polymers sometimes causes plugged
capillaries of refrigerating machines and worsens the compatibility of the
compound with hydrofluorocarbons. Also, the compound requires complicated
post-treatment and cannot always be obtained in high yield because the
vinyl ether monomers, the starting materials of the polyvinyl ether
compound, are not stable substances. In particular, the yield of those
with a low degree of polymerization (around 6) is low. Some vinyl ether
monomers of certain structures cannot be easily obtained, and are,
therefore, very expensive.
As mentioned above, polyvinyl ether compounds show molecular weight
distribution. The products with higher molecular weights sometimes cause
to impair the performance of the compounds. Polyvinyl ether compounds also
have drawbacks of limited availability of the starting materials and poor
yields of those with low degrees of polymerization, which together make
the product cost expensive.
The refrigerant-oil systems developed so far have various drawbacks as
mentioned above. The hydrofluorocarbon-PAG (PAG-OH) oil system has
problems in hygroscopicity and insulating property; and the
hydrofluorocarbon-ester oil system and the hydrofluorocarbon-carbonate oil
system have problems of poor hydrolysis resistance. Both of these systems
are unsatisfactory as a working fluid composition for a refrigerating
machine, because, as compared with the conventional CFC12-mineral oil
system, they have higher hygroscopicity, lower thermal stability, stronger
deteriorating action on organic materials, and stronger effects to corrode
and wear metals. Polyvinyl ether compounds show a molecular weight
distribution and the molecules with high molecular weights cause to lower
the compatibility with hydrofluorocarbons. Polyvinyl ether compounds also
have drawbacks of limited availability of the starting materials and of
high cost.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide novel
polyol ether derivatives that can make an inexpensive base oil for a
working fluid composition for a refrigerating machine, the novel polyol
ether derivatives having excellent compatibility with hydrofluorocarbons,
high thermal stability, strong resistance against hydrolysis, appropriate
kinematic viscosity, good fluidity at low temperatures, and especially
good volume resistivity, thereby solving the above problems.
It is another object of the present invention to provide a method by which
the above polyol ether derivatives are industrially advantageously
produced.
It is still another object of the present invention to provide a working
fluid composition for a refrigerating machine comprising a refrigeration
oil containing, as a base oil, the polyol ether derivatives and a
hydrofluorocarbon.
Known polyol ether derivatives each having an alcohol residue from a
hexahydric alcohol, such as sorbitol and mannitol are hexamethyl ether,
hexavinyl ether, hexaoleyl ether, 1,3,4,5,6-pentamethyl ether (monool),
2,3,4,5,6-pentabenzyl ether (monool), 1,3,5-trimethyl-6-triphenyl methyl
ether (diol), 1,2,5,6-tetrakistetradecyl ether (diol), 1,4,5-triethyl
ether (triol), 2,3,5-trisdodecyl ether (triol), 1,6-didodecyl ether
(tetraol), 2,5-dibenzyl ether (tetraol), 1-t-butyl ether (pentaol), and
1-hexadecyl ether (pentaol).
However, polyol ether derivatives having an ether alkyl group (an alkyl
group bound to an oxygen atom) which is branched at .alpha.-position, i.e.
polyol ether derivatives having secondary or tertiary alkyl groups as an
ether alkyl group; and polyol ether derivatives having branched ether
alkyl groups of 3 to 17 carbon atoms have yet to be known except for those
having t-butyl groups as ether alkyl groups.
As a result of intense research in view of the above objects, the present
inventors have found that polyol ether derivatives having a certain
structure and not having an alkylene oxide group in a molecule can achieve
the above objects.
For producing such polyol ether derivatives, there have been methods in
which a hexahydric alcohol reacts with an alkylating agent, such as a
dialkyl sulfate, an alkyl tosylate, and an alkyl halide. The methods
however have a problem that the desired product cannot be obtained in a
high yield except when the alkyl of alkylating agent is a primary alkyl,
and a problem that by-products such as sulfates and common salt are
produced in high amounts, especially when the degree of etherification is
increased, causing disadvantages in terms of production and economy.
In this situation, the present inventors have found that the polyol ether
derivatives of the present invention can easily be obtained by carrying
out a reaction of a hexahydric alcohol with a carbonyl compound to form an
intermediate cyclic acetal, and hydrogenating or hydrogenating and
alkyl-capping the cyclic acetal to give the polyol ether derivatives.
The present invention has been achieved based upon the above findings.
In brief, the present invention is directed to:
(1) A polyol ether derivative represented by any one of the following
general formulas (I) to (IV):
##STR1##
wherein R.sub.1 represents a hydrogen atom, a linear alkyl group having
1-21 carbon atoms or a branched alkyl group having 3-21 carbon atoms;
R.sub.2 represents a branched alkyl group having 3-17 carbon atoms when
R.sub.1 represents a hydrogen atom, or R.sub.2 represents a linear alkyl
group having 1-21 carbon atoms or a branched alkyl group having 3-21
carbon atoms when R.sub.1 represents a linear alkyl group having 1-21
carbon atoms or a branched alkyl group having 3-21 carbon atoms; R.sub.1
and R.sub.2 may together join to form a ring with an alkylene group having
2-13 carbon atoms; 2 to 6 pairs of R.sub.1 and R.sub.2 may be identical or
different; k.sub.1 represents a number of 0-5, p.sub.1 represents a number
of 0-2, m.sub.1 represents or 1, wherein k.sub.1, p.sub.1 and m.sub.1
satisfy the equation k.sub.1 +(m.sub.1 +2)p.sub.1 =5; k.sub.2 and n.sub.2
each represents a number of 0-4, p.sub.2 represents a number of 0-2,
m.sub.2 represents 0 or 1, wherein k.sub.2, p.sub.2, m.sub.2 and n.sub.2
satisfy the equation k.sub.2 +(m.sub.2 +2)p.sub.2 +n.sub.2 =4; R.sub.3
represents a hydrogen atom, a linear alkyl group having 1-8 carbon atoms
or a branched alkyl group having 3-8 carbon atoms; and repeating units in
formulas (I) and (II), namely methylene groups substituted with
oxygen-containing group (hereinafter, simply referred to as O-methylene
groups) in the number of k.sub.1 and cyclic acetal (or ketal) units in the
number of p.sub.1 in formula (I), and O-methylene groups in the numbers of
k.sub.2 and n.sub.2 and cyclic acetal (or ketal) units in the number of
p.sub.2 in formula (II) may be arranged at random or in block form;
(2) The polyol ether derivative described in (1) above, wherein an alcohol
residue of the polyol ether derivative is derived from sorbitol;
(3) A method for producing a polyol ether derivative represented by any one
of formulas (VII) to (X), comprising the steps of:
reacting a hexahydric alcohol represented by the following formula (V):
##STR2##
with a carbonyl compound represented by the following formula (VI):
##STR3##
wherein R.sub.1 represents a hydrogen atom, a linear alkyl group having
1-21 carbon atoms or a branched alkyl group having 3-21 carbon atoms; and
R.sub.2 represents a linear alkyl group having 1-21 carbon atoms or a
branched alkyl group having 3-21 carbon atoms, or with a reactive
derivative thereof, i.e., an acetal or a ketal, in the presence of an acid
catalyst to form a cyclic acetal or a cyclic ketal; and
hydrogenating, and optionally further alkylating the cyclic acetal or the
cyclic ketal to give a polyol ether derivative represented by the
following formulas (VII) to (X):
##STR4##
wherein R.sub.1 represents a hydrogen atom, a linear alkyl group having
1-21 carbon atoms or a branched alkyl group having 3-21 carbon atoms;
R.sub.2 represents a linear alkyl group having 1-21 carbon atoms or a
branched alkyl group having 3-21 carbon atoms; R.sub.1 and R.sub.2 may
together join to form a ring with an alkylene group having 2-13 carbon
atoms; 2 to 6 pairs of R.sub.1 and R.sub.2 may be identical or different;
k.sub.1 represents a number of 0-5, p.sub.1 represents a number of 0-2,
m.sub.1 represents 0 or 1, wherein k.sub.1, p.sub.1 and m.sub.1 satisfy
the equation k.sub.1 +(m.sub.1 +2)p.sub.1 =5; k.sub.2 and n.sub.2 each
represents a number of 0-4, pa represents a number of 0-2, m.sub.2
represents 0 or 1, wherein k.sub.2, p.sub.2, m.sub.2 and n.sub.2 satisfy
the equation k.sub.2 +(m.sub.2 +2)p.sub.2 +n.sub.2 =4; R.sub.3 represents
a hydrogen atom, a linear alkyl group having 1-8 carbon atoms or a
branched alkyl group having 3-8 carbon atoms; and repeating units in
formulas (VII) and (VIII), namely O-methylene groups in the number of
k.sub.1 and cyclic acetal (or ketal) units in the number of p.sub.1 in
formula (VII), and O-methylene groups in the number of k.sub.2 and n.sub.2
and cyclic acetal (or ketal) units in the number of p.sub.2 in formula
(VIII) may be arranged at random or in block form;
(4) The method described in (3) above, wherein the hexahydric alcohol
represented by formula (V) is sorbitol;
(5) The method described in (3) or (4) above, wherein, in formulas (VII) to
(X), R.sub.1 represents a hydrogen atom and R.sub.2 represents a linear
alkyl group having 1-13 carbon atoms or a branched alkyl group having 3-13
carbon atoms, or wherein R.sub.1 and R.sub.2 in formulas (VII) to (X) each
represents a linear alkyl group having 1-13 carbon atoms or a branched
alkyl group having 3-13 carbon atoms;
(6) A working fluid composition for a refrigerating machine, comprising a
hydrofluorocarbon and a refrigeration oil containing a polyol ether
derivative represented by the following formula (XI) as a base oil:
##STR5##
wherein R.sup.1 to R.sup.6 may be identical or different, each
representing a linear alkyl group having 1-14 carbon atoms, a branched
alkyl group having 3-14 carbon atoms or a cyclic alkyl group having 3-14
carbon atoms and the total number of carbon atoms of R.sup.1 to R.sup.6
being 8 to 40;
(7) The working fluid composition for a refrigerating machine described in
(6) above, wherein a hexahydric alcohol residue of the compound
represented by formula (XI) is derived from sorbitol;
(8) The working fluid composition for a refrigerating machine described in
(6) or (7) above, wherein the compound represented by formula (XI) is
synthesized by the steps of:
reacting a hexahydric alcohol represented by the following formula (V):
##STR6##
with (a) one or more carbonyl compounds represented by the following
formula (XII) for ketalization or acetalization:
##STR7##
wherein R.sup.7 represents a hydrogen atom, a linear alkyl group having
1-13 carbon atoms, a branched alkyl group having 3-13 carbon atoms or a
cyclic alkyl group having 3-13 carbon atoms, and R.sup.8 represents a
linear alkyl group having 1-13 carbon atoms, a branched alkyl group having
3-13 carbon atoms or a cyclic alkyl group having 3-13 carbon atoms with
the proviso that R.sup.7 and/or R.sup.8 have at least one hydrogen atom at
.alpha.-position to the carbonyl group, and the total number of carbon
atoms of R.sup.7 and R.sup.8 is 1-13; and R.sup.7 and R.sup.8 may together
join to form a ring with an alkylene group having 2-13 carbon atoms, or
with (b) reactive derivatives of the carbonyl compounds (ketal or acetal)
for transketalization or transacetalization to obtain a cyclic ketal or a
cyclic acetal;
hydrogenating the cyclic ketal or the cyclic acetal to obtain a polyol
ether; and
alkylating the polyol ether to give a polyol ether derivative;
(9) The working fluid composition for a refrigerating machine described in
(6) or (7) above, which further comprises one or more compounds selected
from the group consisting of (a) 0.05 to 2.0 parts by weight of an epoxy
compound, (b) 0.01 to 100 parts by weight of an orthoester compound, (c)
0.01 to 100 parts by weight of acetal or ketal, and (d) 0.05 to 5 parts by
weight of carbodiimide, each amount of (a) to (d) being based on 100 parts
by weight of the polyol ether derivative represented by formula (XI);
(10) The working fluid composition for a refrigerating machine described in
(8) above, which further comprises one or more compounds selected from the
group consisting of (a) 0.05 to 2.0 parts by weight of an epoxy compound,
(b) 0.01 to 100 parts by weight of an orthoester compound, (c) 0.01 to 100
parts by weight of acetal or ketal, and (d) 0.05 to 5 parts by weight of
carbodiimide, each amount of (a) to (d) being based on 100 parts by weight
of the polyol ether derivative represented by formula (XI);
(11) A Working fluid composition for a refrigerating machine, comprising a
hydrofluorocarbon and a refrigeration oil containing as a base oil a
polyol ether derivative represented by the following formula (XIII.sub.AA)
or (XIII.sub.BB):
##STR8##
wherein R.sup.1 to R.sup.6 may be identical or different, each
representing a linear alkyl group having 1-14 carbon atoms, a branched
alkyl group having 3-14 carbon atoms or a cyclic alkyl group having 3-14
carbon atoms; R.sup.7 represents an hydrogen atom, or a linear alkyl group
having 1-13 carbon atoms, a branched alkyl group having 3-13 carbon atoms
or a cyclic alkyl group having 3-13 carbon atoms; R.sup.8 represents a
linear alkyl group having 1-13 carbon atoms, a branched alkyl group having
3-13 carbon atoms or a cyclic alkyl group having 3-13 carbon atoms;
R.sup.7 and R.sup.8 may together join to form a ring with an alkylene
group having 2-13 carbon atoms; the total number of carbon atoms is 8-40
for R.sup.1, R.sup.2, R.sup.3, R.sup.6, R.sup.7 and R.sup.8 in formula
(XIII.sub.AA), and for R.sup.1, R.sup.4, R.sup.5, R.sup.6, R.sup.7 and
R.sup.8 in formula (XIII.sub.BB), and is 1-13 for R.sup.7 and R.sup.8 in
formulas (XIII.sub.AA and XIII.sub.BB); and "a" to "e" are symbols for
structure unit, and may be arranged in any sequential order;
(12) The working fluid composition for a refrigerating machine described in
(11) above, wherein a hexahydric alcohol residue of the compound
represented by formula (XIII.sub.AA) or (XIII.sub.BB) is derived from
sorbitol;
(13) The working fluid composition for a refrigerating machine described in
(11) or (12) above, wherein the compound represented by formula
(XIII.sub.AA) or (XIII.sub.BB) is synthesized by the steps of:
reacting a hexahydric alcohol represented by the following formula (V):
##STR9##
with (a) one or more carbonyl compounds represented by the following
formula (XII) for ketalization or acetalization:
##STR10##
wherein R.sup.7 represents a hydrogen atom, a linear alkyl group having
1-13 carbon atoms, a branched alkyl group having 3-13 carbon atoms or a
cyclic alkyl group having 3-13 carbon atoms, and R.sup.8 represents a
linear alkyl group having 1-13 carbon atoms, a branched alkyl group having
3-13 carbon atoms, or a cyclic alkyl group having 3-13 carbon atoms with
the proviso that R.sup.7 and/or R.sup.8 have at least one hydrogen atom at
.alpha.-position to the carbonyl group, and the total number of carbon
atoms of R.sup.7 and R.sup.8 is 1-13; and R.sup.7 and R.sup.8 may together
join to form a ring with an alkylene group having 2-13 carbon atoms; or
with (b) reactive derivatives of the carbonyl compounds (ketal or acetal)
thereof for transketalization or transacetalization to obtain a cyclic
ketal or a cyclic acetal;
hydrogenating the cyclic ketal or the cyclic acetal to obtain a polyol
ether ketal or a polyol ether acetal; and
alkylating the polyol ether ketal or the polyol ether acetal;
(14) The working fluid composition for a refrigerating machine described in
(11) or (12) above, which further comprises one or more compounds selected
from the group consisting of (a) 0.05 to 2.0 parts by weight of an epoxy
compound, (b) 0.01 to 100 parts by weight of an orthoester compound, (c)
0.01 to 100 parts by weight of an acetal or a ketal, and (d) 0.05 to 5
parts by weight of carbodiimide, each amount of (a) to (d) being based on
100 parts by weight of the polyol ether derivative represented by formula
(XIII.sub.AA) or (XIII.sub.BB);
(15) The working fluid composition for a refrigerating machine described in
(13) above, which further comprises one or more compounds selected from
the group consisting of (a) 0.05 to 2.0 parts by weight of an epoxy
compound, (b) 0.01 to 100 parts by weight of an orthoester compound, (c)
0.01 to 100 parts by weight of an acetal or a ketal, and (d) 0.05 to 5
parts by weight of carbodiimide, each amount of (a) to (d) being based on
100 parts by weight of the polyol ether derivative represented by formula
(XIII.sub.AA) or (XIII.sub.BB);
(16) The working fluid composition for a refrigerating machine described in
(6) or (11) above, wherein the polyol ether derivative has an average
molecular weight in the range of from 200 to 800;
(17) The working fluid composition for a refrigerating machine described in
(6) or (11) above, wherein the polyol ether derivative has an average
molecular weight in the range of from 300 to 700;
(18) The working fluid composition for a refrigerating machine described in
(6) or (11) above, wherein the polyol ether derivative has a viscosity at
100.degree. C. of from 0.5 to 30 mm.sup.2 /s; and
(19) The working fluid composition for a refrigerating machine described in
(6) or (11) above, wherein the polyol ether derivative has a viscosity at
40.degree. C. of from 1 to 300 mm.sup.2 /s.
According to the present invention, novel and useful polyol ether
derivatives usable for preparation of synthetic lubricating oils and other
various purposes can be produced from inexpensive starting materials by
simple process.
A working fluid composition for a refrigerating machine comprising a
hydrofluorocarbon and a refrigeration oil containing as a base oil novel
polyol ether derivative of the present invention has the following
excellent properties: good compatibility, good thermal stability, high
hydrolysis resistance, adequate kinematic viscosity, good fluidity at low
temperatures, and noticeably high volume resistivity. Thus, a working
fluid composition for a refrigerating machine of the present invention can
suitably be used for motor-integrated compression refrigerating machines
used for refrigerators and room air conditioners.
DETAILED DESCRIPTION OF THE INVENTION
Here, for the sake of convenience, the present invention will be described
in more detail according to the following three parts: (1) Novel polyol
ether derivatives; (2) A novel method for producing polyol ether
derivatives; and (3) A working fluid composition for a refrigerating
machine comprising a refrigeration oil containing as a base oil polyol
ether derivatives and a hydrofluorocarbon. In the present specification,
substituent groups in the formulas are defined for each formula.
Therefore, it should be noted that the definition for R.sub.2, for
example, is different between formulas (I)-(IV) and formulas (VI)-(X) and
that it is interpreted differently between these two groups of formulas.
Also, it should be noted that superior figures (e.g., R.sup.2) in formulas
(XI), (XIII.sub.AA) and (XIII.sub.BB) are used to clearly indicate that
these substituents are defined differently from those in the other
formulas (i.e., formulas (I) to (IV) and (VI) to (X)) where inferior
figures (e.g., R.sub.2) are used.
(1) Novel polyol ether derivatives
The novel polyol ether derivatives of the present invention are represented
by any one of formulas (I) to (IV).
In formulas (I) to (IV), R.sub.1 represents a hydrogen atom, a linear alkyl
group having 1-21 carbon atoms or a branched alkyl group having 3-21
carbon atoms. Examples of the linear alkyl groups having 1-21 carbon atoms
include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl,
undecyl, tridecyl, pentadecyl, heptadecyl, nonadecyl, and heneicosyl; and
examples of branched alkyls having 3-21 carbon atoms include
1-methyloctadecyl, 1-decylundecyl, and 2-methyleicosyl in addition to the
branched alkyls having 3-17 carbon atoms exemplified below.
In formulas (I) to (IV), when R.sub.1 represents a hydrogen atom, R.sub.2
represents a branched alkyl having 3-17 carbon atoms, preferably 3-12
carbon atoms. Branched alkyls having 3-17 carbon atoms represented by
R.sub.2 are exemplified below.
Examples of .alpha.-methyl-branched alkyls include isopropyl,
1-methylpropyl, 1-methylbutyl, 1-methylpentyl, 1-methylhexyl,
1-methylheptyl, 1-methyloctyl, 1-methylnonyl, 1-methyldecyl,
1-methylundecyl, and 1-methylhexadecyl.
Examples of other .alpha.-branched alkyls include 1-ethylpropyl,
1-ethylbutyl, 1-ethylpentyl, 1-propylbutyl, 1-ethylhexyl, 1-propylpentyl,
1-ethylheptyl, 1-propylhexyl, 1-butylpentyl, 1-pentylhexyl, 1-hexylheptyl,
1-octylnonyl, and 1-hexylundecyl. Examples of cyclic alkyls branched at
.alpha.-position include cyclopentyl, cyclohexyl,
3-(2',2',5'-trimethylcyclohexyl)propyl, and 1-cyclohexylmethyl.
Examples of .alpha.- and other polybranched alkyls having one or more
branches at positions other than .alpha.-position include
1,2-dimethylpropyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl,
1-ethyl-2-methylpropyl, diisopropylmethyl, 1,4-dimethylpentyl,
1-isopropylbutyl, 1,3,3-trimethylbutyl, 1,5-dimethylhexyl,
1-ethyl-2-methylpentyl, 1-butyl-2-methylpropyl, 1-ethyl-3-methylpentyl,
diisobutylmethyl, and 1,5,9-trimethyldecyl.
Examples of .beta.-branched alkyls include 2-methylpropyl, 2-methylbutyl,
2-methylpentyl, 2-ethylbutyl, 2-methylhexyl, 2-ethylpentyl,
2-methylheptyl, 2-ethylhexyl, and 2-propylpentyl.
Examples of .beta.- and other polybranched alkyls having one or more
branches at positions other than .alpha.- and .beta.-positions include
2,3-dimethylbutyl, 2,4,4-trimethylpentyl, and 2-isopropyl-5-methylhexyl.
Examples of other branched alkyls having one or more branches at positions
other than .alpha.- and .beta.-positions include 3-methylbutyl,
3-methylpentyl, 4-methylpentyl, 3,3-dimethylbutyl, 3-methylhexyl,
4-methylhexyl, 5-methylhexyl, 3,5,5-trimethylhexyl, isodecyl,
3,7-dimethyloctyl, and isoheptadecyl.
Examples of alkyls having a tertiary carbon with no hydrogen atom at
.beta.-position include 2,2-dimethylpropyl, 2,2-dimethylbutyl,
2,2-dimethylbutyl, 1,2,2-trimethylpropyl, 1-ethyl-2,2-dimethylpropyl,
2,2-dimethylpentyl, and 2,3-dimethyl-2-isopropylbutyl.
In formulas (I) to (IV), when R.sub.1 represents a linear alkyl group
having 1-21 carbon atoms or a branched alkyl group having 3-21 carbon
atoms, R.sub.2 represents a linear alkyl group having 1-21 carton atoms or
a branched alkyl group having 3-21 carbon atoms. Preferably, R.sub.1 and
R.sub.2 independently represent a linear alkyl group having 1-12 carbon
atoms or a branched alkyl group having 3-12 carbon atoms. Examples of the
linear alkyl groups having 1-21 carbon atoms represented by R.sub.2 are
the same as those exemplified above for R.sub.1.
Alternatively, R.sub.1 and R.sub.2 may together join to form a ring with an
alkylene group having 2-13 carbon atoms. Examples of alkylene groups
include ethylene, trimethylene, tetramethylene, pentamethylene,
hexamethylene, 1-methyltetramethylene, 2-methyltetramethylene,
1-methylpentamethylene, 2-methylpentamethylene, 3-methylpentamethylene,
1,3-dimethylpentamethylene, 1,5-dimethylpentamethylene,
2,2,4-trimethylpentamethylene, 1-tert-butylpentamethylene,
3-tert-butylpentamethylene, 1-isopropyl-3-methylpentamethylene, and
nonamethylene groups. Examples of linear alkyl group having 1-8 carbon
atoms or a branched alkyls having 3-8 carbon atoms represented by R.sub.3
include methyl, ethyl, propyl, butyl, isobutyl, hexyl, and 2-ethylhexyl,
with a preference given to methyl or ethyl.
Of the polyol ether derivatives represented by formulas (I) to (IV), those
of which alcohol residue is derived from sorbitol are preferable.
The following are examples (compound names and structures) of polyol ether
derivatives represented by formulas (I) to (IV), but the present invention
are not limited to the examples:
1,6-di-O-(1-methylethyl)sorbitol
##STR11##
2,4,5-tri-O-methyl-1,3,6-tri-O-(3,5,5-trimethylhexyl)sorbitol
##STR12##
(R: 3,5,5-trimethylhexyl group)
1,6-di-O-(1-methylbutyl)-3,4-O-(1-methylbutylidene)sorbitol
##STR13##
(2) Novel method for producing polyol ether derivatives
A method of the present invention comprises the steps of reacting a
hexahydric alcohol represented by formula (V) with a carbonyl compound
(ketone or aldehyde) or with a reactive derivative thereof (ketal or
acetal) in the presence of acid catalyst to form a cyclic acetal or ketal;
and hydrogenating, or hydrogenating and further alkylating the cyclic
acetal or ketal to give polyol ether derivatives represented by formulas
(VII) to (X). Here, "alkylating" means a reaction that may also be
referred to as "alkyl-capping." The reactions proceed as shown in the
following steps:
##STR14##
In the above formulas, R.sub.1 represents a hydrogen atom, a linear alkyl
group having 1-21 carbon atoms or a branched alkyl group having 3-21
carbon atoms. When R.sub.1 is a hydrogen atom, R.sub.2 is a linear alkyl
group having 1-21 carbon atoms or a branched alkyl group having 3-21
carbon atoms, preferably a linear alkyl group having 1-17 carbon atoms or
a branched alkyl group having 3-17 carbon atoms, more preferably a linear
alkyl group having 1-18 carbon atoms or a branched alkyl group having 3-18
carbon atoms. When R.sub.1 is a linear alkyl group having 1-21 carbon
atoms or a branched alkyl group having 3-21 carbon atoms, R.sub.2 is a
linear alkyl group having 1-21 carbon atoms or a branched alkyl group
having 3-21 carbon atoms. It is preferable that both R.sub.1 and R.sub.2
independently are a linear alkyl group having 1-13 carbon atoms or a
branched alkyl group having 3-13 carbon atoms.
Examples of linear alkyl groups having 1-8 carbon atoms or a branched alkyl
groups having 3-8 carbon atoms represented by R.sub.3 include methyl,
ethyl, propyl, butyl, isobutyl, hexyl, and 2-ethylhexyl, with a preference
given to methyl or ethyl.
R.sub.4 represents a linear alkyl group having 1-6 carbon atoms or a
branched alkyl group having 3-6 carbon atoms. Y represents a residue of an
alkylating agent.
In brief, the polyol ether derivatives of the present invention are
produced by the following steps:
reacting a hexahydric alcohol such as sorbitol and mannitol represented by
formula (V) with a carbonyl compound such as a ketone and an aldehyde
represented by formula (VI) for dehydration, or with a reactive derivative
thereof represented by formula (2-VI') for dealcoholization, both in the
presence of acid catalyst to give a cyclic acetal or ketal represented by
formula (2-XIV); and
hydrogenating the cyclic acetal or ketal to give a polyol ether or a polyol
ether acetal or ketal (here, "polyol ether acetal or ketal" means
partially etherified and partially acetalized or ketalized polyol); or
further alkylating the polyol ether or the polyol ether acetal or ketal to
give an alkylated (alkyl-capped) ether represented by formulas
(2-XVI.sub.A) and (2-XVI.sub.B) after hydrogenation as mentioned above.
The starting materials used in the above-mentioned reactions will be
described in detail.
Hexahydric alcohol
Examples of hexahydric alcohols usable in the present invention are those
represented by formula (V), which include hexytols obtained by reducing
hexoses, such as sorbitol, mannitol, galactitol, iditol, talitol, and
allitol. From the view point of availability and cost, sorbitol is the
most preferable.
Carbonyl compound
The carbonyl compounds usable in the present invention and represented by
formula (VI) are ketones and aldehydes. Ketones are readily obtained by
high temperature decarboxylating dimerization of fatty acids, catalytic
oxidation of olefins (Wacker process), oxidation-dehydrogenation of
secondary alcohols, and oxidation of cycloalkanes. Ketones obtained by
Wacker process show a molecular weight distribution, but they can be
separated and purified by rectification. The ketones usable in the present
invention are exemplified below, but not limited to these examples.
Examples of methyl alkyl ketones include acetone, methyl ethyl ketone,
methyl propyl ketone, methyl butyl ketone, methyl amyl ketone, methyl
hexyl ketone, methyl heptyl ketone, methyl octyl ketone, methyl nonyl
ketone, methyl undecyl ketone, and methyl heptadecyl ketone.
Examples of dialkyl ketones include diethyl ketone, ethyl propyl ketone,
ethyl butyl ketone, dipropyl ketone, ethyl pentyl ketone, ethyl hexyl
ketone, dibutyl ketone, depentyl ketone, dihexyl ketone, diundecyl ketone,
and diheptadecyl ketone.
Examples of polybranched ketones include methyl isopropyl ketone, methyl
sec-butyl ketone, methyl isobutyl ketone, ethyl isopropyl ketone, methyl
tert-butyl ketone, diisopropyl ketone, methyl isoamyl ketone, isopropyl
propyl ketone, methyl neopentyl ketone, ethyl tert-butyl ketone,
6-methyl-2-heptanone, 4-methyl-3-heptanone, 2-methyl-3-heptanone,
5-methyl-3-heptanone, diisobutyl ketone, and 6,10-dimethyl-2-undecanone.
Examples of cyclic ketones include cyclopropanone, cyclobutanone,
cyclopentanone, cyclohexanone, 2-methyl cyclopentanone,
3-methylcyclopentanone, 2-methylcyclohexanone, 3-methylcyclohexanone,
4-methylcyclohexanone, cycloheptanone, 2,4-dimethylcyclohexanone,
2,6-dimethylcyclohexanone, 3,3,5-trimethylcyclohexanone,
2-tert-butylcyclohexanone, 4-tert-butylcyclohexanone,
2-isopropyl-4-methylcyclohexanone, and cyclodecanone.
Examples of cyclic alkyl ketones include methyl cyclohexyl ketone, and
5-(2',2',5'-trimethylcyclohexyl)-2-pentanone.
Aldehydes used in the present invention are those readily prepared by the
following methods: dehydrogenation of fatty alcohols, hydroformylation of
olefins (oxo method), Rosenmund reduction of fatty acid chlorides, and
direct hydrogenation of fatty acids. In the case of the oxo method, both
linear and branched aldehydes are produced, but they can be separated and
purified by rectification.
The aldehydes mentioned below are just examples usable in the present
invention and are not limitative.
Examples of linear alkyl aldehydes include acetaldehyde, propionaldehyde,
butyraldehyde, valeraldehyde, caproaldehyde, heptanal, octanal, decanal,
dodecanal, tetradecanal, octadecanal, and behenaldehyde.
Examples of .alpha.-branched alkyl aldehydes include isobutyraldehyde,
2-methylbutyraldehyde, 2-methylpentanal, 2-ethylbutanal, 2-methylhexanal,
2-ethylpentanal, 2-methylheptanal, 2-ethylhexanal, and 2-propylpentanal.
Examples of .alpha.- and other polybranched alkyl aldehydes having one or
more branches at positions other than .alpha.-position include
2,3-dimethylbutanal, 2,4,4-trimethylpentanal, and
2-isopropyl-5-methylhexanal.
Other examples of other branched alkyl aldehydes having one or more
branches at positions other than .alpha.-position include
isovaleraldehyde, 3-methylpentanal, 4-methylpentanal, 3,3-dimethylbutanal,
3-methylhexanal, 4-methylhexanal, 5-methylhexanal, 3,5,5-trimethylhexanal,
isodecylaldehyde, 3,7-dimethyloctanal, and isooctadecanal.
Examples of cyclic alkyl aldehydes include cyclopentylacetaldehyde, and
cyclohexylacetaldehyde.
Reactive derivatives of carbonyl compounds
Reactive derivatives of carbonyl compounds used in the present invention
are ketals and acetals represented by formula (2-VI') which can readily be
obtained by the reaction of a ketone or aldehyde as mentioned above with a
lower alcohol having 1-6 carbon atoms in the presence of an acid catalyst.
Examples of lower alcohols having 1-6 carbon atoms which give R.sub.4
residue include methanol, ethanol, propanol, isopropanol, butanol,
isobutanol, sec-butanol, tert-butanol, amyl alcohol, isoamyl alcohol,
neopentyl alcohol, 1-methylbutanol, 1,1-dimethylpropanol, 1-ethylpropanol,
hexanol, isohexanol, 2-ethylbutanol, 1-methylamyl alcohol,
1,3-dimethylbutanol, and 1-ethylbutanol.
Ketalization
In the present invention, the reaction between a hexahydric alcohol
represented by formula (V) and a ketone is ketalization. The molar ratio
of the ketone to the hexahydric alcohol is in the range of from 1 to 15,
preferably from 1.5 to 7.5. This reaction requires an acidic catalyst,
such as p-toluenesulfonic acid, methanesulfonic acid, and sulfuric acid in
an amount of 0.05 to 10 mole %, preferably 0.1 to 7 mole %, and more
preferably 0.5 to 5 mole % to the amount of the hexahydric alcohol
represented by formula (V).
The above reaction may be carried out with or without solvents. Solvents
usable in the present invention include inert solvents, such as xylene,
toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane,
pentane, ligroin, and petroleum ether. These solvents are used singly or
in combination. The reaction temperature depends upon the boiling point of
the ketone used, and the reaction is normally carried out at a temperature
of from 40.degree. to 160.degree. C., preferably from 60.degree. to
100.degree. C., while removing the water formed in the process of the
reaction. There are also some cases where the reaction can effectively be
carried out under a reduced pressure. In the above temperature range, the
reaction can favorably proceed and coloration due to side reactions is
less likely to occur. Also, the reaction may be carried out in a nitrogen
stream, nitrogen atmosphere, or dry air. The reaction time varies with
reaction conditions employed, but it is generally preferred to continue
the reaction for 5 to 200 hours. The cyclic ketals obtained (2-XIV) are
neutralized and subjected to pretreatments, such as filtration and
washing. Then, the ketals can be purified by such means as adsorption,
crystallization, and distillation.
Acetalization
In the present invention, the reaction between a hexahydric alcohol
represented by formula (V) and an aldehyde is acetalization. The molar
ratio of the aldehyde to the hexahydric alcohol is in the range of from 1
to 6, preferably from 1.5 to 3.8. This reaction requires an acidic
catalyst, such as p-toluenesulfonic acid, methanesulfonic acid, and
sulfuric acid, in an amount of 0.01 to 5 mole %, preferably 0.05 to 3 mole
%, and more preferably 0.1 to 2 mole % to the amount of the hexahydric
alcohol represented by formula (V).
The above reaction may be carried out with or without solvents. Solvents
usable in the present invention include inert solvents, such as xylene,
toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane,
pentane, ligroin, and petroleum ether. These solvents are used singly or
in combination. The reaction temperature depends upon the boiling point of
the aldehyde used, and the reaction is normally carried out at a
temperature of from 20.degree. to 130.degree. C., preferably from
40.degree. to 100.degree. C., while removing the water in the process of
the reaction. There are also some cases where the reaction can effectively
proceed under a reduced pressure. In the above temperature range, the
reaction can favorably proceed and coloration due to side reactions is
less likely to occur. Also, the reaction may be carried out in a nitrogen
stream, nitrogen atmosphere, or dry air. The reaction time varies with
reaction conditions employed, but it is generally preferred to continue
the reaction for 1 to 30 hours. The cyclic acetals obtained (2-XIV) are
neutralized and subjected to pretreatments, such as filtration and
washing. Then, the acetals can be purified by conventional means, such as
adsorption, crystallization, and distillation.
Transketalization
In the present invention, the reaction between a hexahydric alcohol
represented by formula (V) and a ketal (2-VI'), a reactive derivative of
ketone, is transketalization. The molar ratio of the ketal to the
hexahydric alcohol is in the range of from 1 to 15, preferably from 1.5 to
7.5. This reaction requires an acidic catalyst, such as p-toluenesulfonic
acid, methanesulfonic acid, and sulfuric acid, in an amount of 0.05 to 10
mole %, preferably 0.1 to 7 mole %, and more preferably 0.5 to 5 mole % to
the amount of the hexahydric alcohol represented by formula (V).
The above reaction may be carried out with or without solvents. Solvents
usable in the present invention include inert solvents, such as xylene,
toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane,
pentane, ligroin, and petroleum ether. These solvents are used singly or
in combination. Though the reaction temperature depends upon the boiling
points of the ketal (2-VI') used and the lower alcohol formed, the
reaction is carried out at a temperature of from 40.degree. to 160.degree.
C., preferably from 60.degree. to 130.degree. C., while removing the lower
alcohol formed in the process of the reaction. There are also some cases
where the reaction can effectively be carried out under a reduced
pressure. In the above temperature range, the reaction can favorably
proceed and coloration due to side reactions is less likely to occur.
Also, the reaction may be carried out in a nitrogen stream, nitrogen
atmosphere, or dry air. The reaction time varies with reaction conditions
employed, but it is generally preferred to continue the reaction for 5 to
200 hours. The cyclic ketals obtained (2-XIV) are neutralized and
subjected to pretreatments, such as filtration and washing. Then, the
cyclic ketals can be purified by conventional means, such as adsorption,
crystallization, and distillation.
Transacetalization
In the present invention, the reaction between a hexahydric alcohol
represented by formula (V) and an acetal (2-VI'), a reactive derivative of
aldehyde, is transacetalization. The molar ratio of the acetal (2-VI') to
the hexahydric alcohol is in the range of from 1.5 to 6, preferably from
2.7 to 3.8. This reaction requires an acidic catalyst, such as
p-toluenesulfonic acid, methanesulfonic acid, and sulfuric acid, in an
amount of 0.01 to 5 mole %, preferably 0.05 to 3 mole %, and more
preferably 0.1 to 2 mole % to the amount of the hexahydric alcohol
represented by formula (V).
The above reaction may be carried out with or without solvents. Solvents
usable in the present invention include inert solvents, such as xylene,
toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane,
pentane, ligroin, and petroleum ether. These solvents are used singly or
in combination. The reaction temperature depends upon the boiling points
of the acetal used and the lower alcohol formed, and the reaction is
normally carried out at a temperature of from 20.degree. to 150.degree.
C., preferably from 40.degree. to 130.degree. C., while removing the lower
alcohol formed in the process of the reaction. There are also some cases
where the reaction can effectively proceed under a reduced pressure. In
the above temperature range, the reaction can favorably proceed and
coloration due to side reactions is less likely to occur. Also, the
reaction may be carried out in a nitrogen stream, nitrogen atmosphere, or
dry air. The reaction time varies with reaction conditions employed, but
it is generally preferred to continue the reaction for 1 to 30 hours. The
cyclic acetals obtained (2-XIV) are neutralized and subjected to
pretreatments, such as filtration and washing. Then, the acetals can be
purified by conventional means, such as adsorption, crystallization, and
distillation.
Hydrogenation
The hydrogenation of the cyclic ketal or cyclic acetal represented by
formula (2-XIV) can be carried out using a conventional hydrogenolysis
catalyst, such as palladium, rhodium, ruthenium, and platinum, in an
amount of from 5 to 5000 ppm to the amount of cyclic acetal or cyclic
ketal, under normal to 250 kg/cm.sup.2 of hydrogen pressure, at a
temperature of from 50.degree. to 250.degree. C., for 1 to 30 hours. The
above hydrogenolysis catalysts may be carried on the surface of carriers,
such as carbon, alumina, silica, diatomaceous earth, and titanium oxide,
at a ratio of 0.1 to 20%. As for hydrogenolysis catalyst, palladium,
especially having a pH of 5 to 8, is particularly preferable. It is also
preferred to remove moisture from the catalyst before use. This reaction
may be carried out with or without solvents. When a solvent is used, the
following inert solvents can be used singly or in combination: decane,
octane, isooctane, heptane, hexane, and cyclohexane. The starting
materials of cyclic acetals or ketals, such as hexahydric alcohols
represented by formula (V), aldehydes, and ketones, may be added to the
reaction system. Acidic substances, such as phosphoric acid, may be added
in a slight amount. The reaction may be carried out in a closed system or
under a hydrogen stream.
In this hydrogenation reaction, the bond between carbon and oxygen atoms in
an acetal or ketal is reductively cleaved to give an ether and alcohol,
and intermolecular transformation of acetals or ketals occurs at the same
time. Accordingly, the starting materials of triacetal or triketal
generally can yield a mixture of alkyl ethers with different numbers of
substituents ranging from 1 to 5. In the resulting alkyl ethers having the
same number of substituents, those etherified at 1 and/or 6 positions are
predominant. When the reaction is discontinued on the way, ether alcohols
having acetal or ketal rings can be obtained. When alkyl ethers having a
smaller number of alkyl or alkylidene substituents are to be obtained,
acetals or ketals which are prepared by using an aldehyde or a ketone or a
reactive derivative thereof in an amount smaller than the equivalent of a
hexahydric alcohol may be subjected to the hydrogenation. Alkyl ethers
with a smaller number of substituents can also be obtained by adding a
hexahydric alcohol to a triacetal or a triketal, and carrying out the
hydrogenation reaction.
When alkyl ethers having a smaller number of alkyl substituents and no
acetal or ketal rings are to be obtained, hydrogenation may be
discontinued on the way and hydrolysis is carried out in a methanol or
ethanol aqueous solution using p-toluensulfonic acid, sulfuric acid, or
hydrochloric acid as a catalyst.
When alkyl ethers having a larger number of alkyl substituents are to be
obtained in a larger quantity, an acetal or ketal is further added to the
hydrogenation reaction system.
The thus-obtained mixture of polyol ethers (2-XV.sub.A), the mixture of
polyol ether acetals (2-XV.sub.B), or the mixture of polyol ether ketals
(2-XV.sub.B), each mixture containing hydrogenation products with
different numbers of alkyl substituents, may be subjected to the
subsequent alkylation directly, or, if necessary, after a desired polyol
ether or the like is isolated.
The isolation of a desired polyol ether or the like from the reaction
mixtures can be carried out by conventional means after removing the
catalyst used by filtration. For example, evaporation of solvent, washing,
recrystallization, distillation, and chromatography may be employed solely
or in combination.
Alkylation (alkyl-capping)
Ether compounds represented by formulas (2-XVI.sub.A) and (2-XVI.sub.B) are
obtained by treating the hydroxyl groups of the polyol ethers (2-XV.sub.A)
or polyol ether ketals or acetals (2-XV.sub.B) obtained by the
above-mentioned process with a base, such as Na, NaH, NaOCH.sub.3, NaOH,
and KOH, to give a corresponding alcoholate, and treating the alcoholate
with an alkylating agent, such as an alkyl halide, dialkyl sulfate, and
alkyl tosylate, to alkylate the hydroxyls of the polyol ethers or polyol
ether ketals or acetals.
The alkyl halides used in the above reaction include the following
halogenated lower alkyls: chlorides of linear alkyls, such as methyl
chloride, ethyl chloride, propyl chloride, butyl chloride, amyl chloride,
hexyl chloride, and octyl chloride; chlorides of branched alkyls such as
isopropyl chloride, isobutyl chloride, sec-butyl chloride, isoamyl
chloride, neopentyl chloride, 1-methylbutyl chloride, 1-ethylpropyl
chloride, isohexyl chloride, 2-ethylbutyl chloride, 1-methylamyl chloride,
1-ethylbutyl chloride, and 2-ethylhexyl chloride; bromides of linear
alkyls, such as methyl bromide, ethyl bromide, propyl bromide, butyl
bromide, amyl bromide, and hexyl bromide; bromides of branched alkyls,
such as isopropyl bromide, isobutyl bromide, sec-butyl bromide, isoamyl
bromide, neopentyl bromide, 1-methylbutyl bromide, 1-ethylpropyl bromide,
isohexyl bromide, 2-ethylbutyl bromide, 1-methylamyl bromide, 1-ethylbutyl
bromide, and 2-ethylhexyl bromide; iodides of linear alkyls, such as
methyl iodide, ethyl iodide, propyl iodide, butyl iodide, amyl iodide, and
hexyl iodide; iodides of branched alkyls, such as isopropyl iodide,
isobutyl iodide, sec-butyl iodide, isoamyl iodide, neopentyl iodide,
1-methylbutyl iodide, 1-ethylpropyl iodide, isohexyl iodide, 2-ethylbutyl
iodide, 1-methylamyl iodide, 1,3-dimethylbutyl iodide, and 1-ethylbutyl
iodide. In view of reactivity, a preference is given to primary alkyl
halides. It is also preferred that these alkyl halides have a boiling
point of not higher than 50.degree. C. so that chlorine, bromine or iodine
will not remain after the reaction.
Examples of dialkyl sulfates are the following lower dialkyl sulfates:
linear dialkyl sulfates, such as dimethyl sulfate, diethyl sulfate,
dipropyl sulfate, dibutyl sulfate, diamyl sulfate, and dihexyl sulfate;
and branched dialkyl sulfates, such as diisopropyl sulfate, diisobutyl
sulfate, di-sec-butyl sulfate, diisoamyl sulfate, dineopentyl sulfate,
di(1-methylbutyl)sulfate, di(1-ethylpropyl)sulfate, diisohexyl sulfate,
di(2-ethylbutyl)sulfate, di(1-methylamyl)sulfate, and
di(1-ethylbutyl)sulfate. In view of reactivity, a preference is given to
primary alkyl sulfates.
Examples of alkyl tosylates are the following lower alkyl tosylates: linear
alkyl tosylates, such as methyl tosylate, ethyl tosylate, propyl tosylate,
butyl tosylate, amyl tosylate, and hexyl tosylate; and branched alkyl
tosylates, such as isopropyl tosylate, isobutyl tosylate, sec-butyl
tosylate, isoamyl tosylate, neopentyl tosylate, 1-methylbutyl tosylate,
1-ethylpropyl tosylate, isohexyl tosylate, 2-ethylbutyl tosylate,
1-methylamyl tosylate, 1,3-dimethyl tosylate, and 1-ethylbutyl tosylate.
In view of reactivity, a preference is given to primary alkyl tosylates.
In the alkylation process, the molar ratio of a base to a hydroxyl group of
polyol ethers (2-XV.sub.A) or polyol ether ketals or acetals (2-XV.sub.B)
is 1.0 to 3.0, preferably 1.0 to 1.5; and the molar ratio of an alkylating
agent to the hydroxyl group is 1.0 to 3.0, preferably 1.0 to 1.5. The
alcoholate forming reaction is carried out in an inert solvent or in a
mixture of solvents, the solvents including xylene, toluene, benzene,
octane, isooctane, heptane, hexane, cyclohexane, pentane, ligroin,
petroleum ether, dimethyl sulfoxide, and 1,2-dimethoxydiethane, at a
temperature in the range of from room temperature to 110.degree. C., the
temperature depending on the boiling point and stability of the solvents
used. Then, O-alkylation is carried out by adding an alkylating agent
dropwise at a temperature of from room temperature to 130.degree. C., the
temperature depending on the reactivity of the alkylating agent. The
alcoholate forming reaction is continued for 0.5 to 2 hours. The reaction
time for O-alkylation depends on the degree of exotherm, and it is
continued preferably for 0.5 to 6 hours as long as the exothermic reaction
can be kept under control. After the completion of the reaction,
alcoholates and the alkylating agents which remain unchanged are
decomposed by adding an aqueous solution of an alkali, such as sodium
hydroxide. After the resulting ether compounds represented by formulas
(2-XVI.sub.A) and (2-XVI.sub.B) are subjected to pretreatments, such as
extraction, filtration, and washing, and they are purified by such a means
as adsorption, steaming, dehydration, and distillation.
(3) A working fluid composition for a refrigerating machine comprising a
refrigeration oil containing polyol ether derivatives as a base oil and a
hydrofluorocarbon
The working fluid composition for a refrigerating machine of the present
invention is characterized by comprising polyol ether derivatives
represented by formula (XI) as a base oil of a refrigeration oil.
In formula (XI), R.sup.1 to R.sup.6 may be identical or different, each
representing a linear alkyl group having 1-14 carbon atoms, a branched
alkyl group having 3-14 carbon atoms or a cyclic alkyl group having 3-14
carbon atoms. The total number of carbon atoms of R.sup.1 to R.sup.6 is in
the range of from 8 to 40.
Generally, the compatibility of a compound used as a base oil with a
hydrofluorocarbon becomes better as the polarity increases, whereas the
insulating property becomes better as the polarity decreases. Therefore,
it is important to appropriately balance the polarity of a compound used
as a base oil of a refrigeration oil.
In the case of an alkyl ether having an alcohol residue with a small number
of hydroxyls, e.g., 3 to 4 hydroxyls, it is required for the alkyl group
of the ether to have a larger number of carbon atoms to get an appropriate
viscosity. This makes the polarity of the alkyl ether lower, and thereby
makes the compatibility with a hydrofluorocarbon poor. On the other hand,
in the case of an alkyl ether having an alcohol residue with a large
number of hydroxyls, e.g., 12 to 13 hydroxyls, it is required for the
alkyl group of the ether to have a smaller number of carbon atoms to get
an appropriate viscosity. This makes the polarity of the alkyl ether
higher and thereby makes the insulating property poor. Therefore, an
alcohol residue having 6 hydroxyls is particularly preferable for
appropriately balancing the above factors.
The hexahydric alcohols, which give the hexahydric alcohol residue (the
structure which remains after deleting R.sup.1 O-- to R.sup.6 O-- from
formula (XI)), include the hexahydric alcohols exemplified as the starting
materials set forth in "(2) A novel method for producing polyol ether
derivatives." Among the examples, sorbitol is the most preferable in terms
of availability and cost.
The linear alkyl group having 1-14 carbon atoms, the branched alkyl group
having 3-14 carbon atoms or the cyclic alkyl group having 3-14 carbon
atoms represented by R.sup.1 to R.sup.6 in formula (XI) are those as
exemplified below.
Among the examples of linear alkyl groups having 1-21 carbon atoms or
branched alkyl groups having 3-21 carbon atoms represented by R.sub.1 set
forth in "(1) Novel polyol ether derivatives," those having 1-14 carbon
atoms can be examples of the alkyls represented by R.sup.1 to R.sup.6 in
formula (XI). Also, alkyls having a tertiary and no hydrogen atom at
.alpha.-position can be exemplified by 1,1-dimethylethyl,
1-methylcyclopropyl, 1,1-dimethylpropyl, 1-methylcyclobutyl,
1,1-dimethylbutyl, 1,1,2-trimethylpropyl, 1-methylcyclopentyl,
1,1-dimethylpentyl, 1-methyl-1-ethylbutyl, 1,1-diethylpropyl, and
1,1-diethylbutyl.
Examples of .alpha.-cyclic alkyl groups include cyclopropyl, cyclobutyl,
cyclopentyl, cyclohexyl, cycloheptyl, 2-methylcyclopentyl,
3-methylcyclopentyl, 2-methylcyclohexyl, 3-methylcyclohexyl,
4-methylcyclohexyl, 2,4-dimethylcyclohexyl, 2,6-dimethylcyclohexyl,
3,3,5-trimethylcyclohexyl, 2-tert-butylcyclohexyl, 4-tert-butylcyclohexyl,
2-isopropyl-4-methylcyclohexyl, and cyclodecyl.
Examples of cycloalkyl groups include cyclopentylmethyl, cyclohexylmethyl,
1-methyl-4-(2'2'5'-trimethylcyclohexyl)butyl, and 1-cyclohexylethyl.
Examples of alkyl groups having tert-carbons and no hydrogen atoms at both
.alpha.- and .beta.-positions include 1,1,2,2-tetramethylpropyl,
1,1,2,2-tetramethylbutyl, and 1,1,2,2-tetramethylhexyl.
For satisfactory compatibility with hydrofluorocarbons and insulating
property, the ratio of the total number of carbon atoms to the total
number of oxygen atoms in a molecule (C/O) is preferably in the range of
from 2.5 to 7.5, more preferably 3.0 to 7.0, even more preferably 3.0 to
7.0, and particularly preferably 4.0 to 6.0.
Accordingly, the total number of carbon atoms is normally in the range of 8
to 40, preferably 9 to 39, more preferably 12 to 36, and still more
preferably 18 to 30. When the total number of carbon atoms is less than 8,
it results in poor insulating property; when it is higher than 40,
compatibility with hydrofluorocarbons becomes poor.
In order to get better compatibility with hydrofluorocarbons, branched and
cyclic alkyls are preferred to linear alkyls. Between branched and cyclic
alkyls, a preference is given to branched alkyls. Alkenyls and alkinyls
having unsaturated bonds are not preferable because of poor thermal
stability.
The names and structures of the polyol ether derivatives represented by
formula (XI) are listed below. However, they are not limitative, and
compounds represented by formulas (XIII.sub.AA) and (XIII.sub.BB) are also
included in the polyol ether derivatives of the present invention.
##STR15##
The above polyol ether derivatives represented by formula (XI) can be
produced by various methods, For example, it can be produced by the
reaction of a hexitol alcoholate, a reactive derivative of hexitol, with
an alkyl halide. However, halogen, such as chlorine, bromine or iodine,
undesirably remains in the product obtained by this method, which impairs
thermal stability of the product.
Therefore, the method described above in "(2) Novel method for producing
polyol ether derivatives" is recommended as an economical and simple
method because it does not use compounds having halogen, such as chlorine,
bromine, or iodine.
Specifically, the polyol ether derivatives represented by formula (XI) is
synthesized by the steps of reacting a hexahydric alcohol represented by
formula (V) with one or more carbonyl compounds (ketone or aldehyde)
represented by formula (XII) for ketalization or acetalization, or with
reactive derivatives of the carbonyl compounds (ketal or acetal) for
transketalization or transacetalization to obtain cyclic ketals or cyclic
acetals; hydrogenating the cyclic ketals or the cyclic acetals to obtain
polyol ethers; and alkylating the polyol ethers to give polyol ether
derivatives.
In formula (XII), R.sup.7 represents a hydrogen atom, a linear alkyl group
having 1-13 carbon atoms, a branched alkyl group having 3-13 carbon atoms
or a cyclic alkyl group having 3-13 carbon atoms, and R.sup.8 represents a
linear alkyl group having 1-13 carbon atoms, a branched alkyl group having
3-13 carbon atoms or a cyclic alkyl group having 3-13 carbon atoms with
the proviso that R.sup.7 and/or R.sup.8 have at least one hydrogen atom at
.alpha.-position to the carbonyl group and the total number of carbon
atoms of R.sup.7 and R.sup.8 is 1-13; and R.sup.7 and R.sup.8 may together
join to form a ring with an alkylene group having 2-13 carbon atoms.
The following is an example scheme of the above reaction.
##STR16##
This reaction mainly produces, as a polyol ether (3-XVIII), two-molar
adducts (3-XVIII.sub.A), three-molar adducts (3-XVIII.sub.B), and
four-molar adducts (3-XVIII.sub.C), with small quantities of one-molar
adducts (3-XVIII.sub.D) and five-molar adducts (3-XVIII.sub.E).
##STR17##
In the above formulas, R.sup.1 to R.sup.6 have the same meanings as those
in formula (XI). However, in the above-mentioned reaction scheme, R.sup.1
to R.sup.6 correspond to the residues of the carbonyl compound represented
by formula (XII) or the residues of the reactive derivative thereof, and,
therefore, can be represented by the following formula:
alkyl group: --CHR.sup.7 R.sup.8.
The polyol ethers (3-XVIII) can be separated to the compounds
(3-XVIII.sub.A) to (3-XVIII.sub.E) by conventional methods for
purification, such as distillation, chromatography, or liquid-liquid
extraction. Each of the polyol ethers (3-XVIII.sub.A) to (3-XVIII.sub.E)
may be separately subjected to alkylation, or the mixture of the polyol
ethers may be alkylated without separation.
Examples of usable hexahydric alcohols represented by formula (V) are
hexitols obtained by reducing hexoses as mentioned above in "(2) A novel
method for producing polyol ether derivatives," the hexitol including
sorbitol, mannitol, galactitol, iditol, talitol, and allitol.
Usable carbonyl compounds represented by formula (XII) are carbonyl
compounds having 2-14 carbon atoms including the carbonyl carbon atom,
examples of which are set forth in "(2) A novel method for producing
polyol ether derivatives."
The method for producing the polyol ether derivatives as mentioned above in
"(2) Novel method for producing polyol ether derivatives" can be employed.
In the hydrogenation reaction, intermediate substances, such as polyol
ether ketals and polyol ether acetals, are produced. Examples of such
intermediate compounds are represented by the following formulas
(3-XIX.sub.A) to (3-XIX.sub.C), the compounds having one or more ether
bonds as well as one or more ketal or acetal rings in a molecule.
##STR18##
When the polyol ethers (3-XVIII) are obtained as a mixture containing the
polyol ether ketals or polyol ether acetals (3-XIX.sub.A to 3-XIX.sub.C),
the polyol ethers containing no ketal or acetal rings (3XVIII) can be
obtained by hydrolysis. Specifically, the mixture obtained is filtered,
and volatile materials in the filtrate are evaporated. The residue is then
subjected to hydrolysis in a mixed acidic solution consisting of an
adequate amount of acid catalyst, such as 0.1 to 1N hydrochloric acid and
ethanol.
Also, the mixture of the polyol ethers (3-XVIII) containing those having
ketal or acetal rings may be directly subjected to the subsequent
alkylation. The polyol ether ketals or polyol ether acetals (3-XIX.sub.A
to 3-XIX.sub.C) are alkylated to form the ether compounds as represented
by formulas (XIII.sub.AA) and (XIII.sub.BB).
In formulas (XIII.sub.AA) and (XIII.sub.BB), R.sup.1 to R.sup.6 may be
identical or different, each representing a linear alkyl group having 1-14
carbon atoms, a branched alkyl group having 3-14 carbon atoms or a cyclic
alkyl group having 3-14 carbon atoms; R.sup.7 represents an hydrogen atom,
or a linear alkyl group having 1-13 carbon atoms, a branched alkyl group
having 3-13 carbon atoms or a cyclic alkyl group having 3-13 carbon atoms;
R.sup.8 represents a linear alkyl group having 1-13 carbon atoms, a
branched alkyl group having 3-13 carbon atoms or a cyclic alkyl group
having 3-13 carbon atoms; R.sup.7 and R.sup.8 may together join to form a
ring with an alkylene group having 2-13 carbon atoms; the total number of
carbon atoms is 8-40 for R.sup.1, R.sup.2, R.sup.3, R.sup.6, R.sup.7 and
R.sup.8 in formula (XIII.sub.AA), and for R.sup.1, R.sup.4, R.sup.5,
R.sub.6, R.sup.7 and R.sup.8 in formula (XIII.sub.BB), and is 1-13 for
R.sup.7 and R.sup.8 for both formulas; and "a" to "e" are symbols for
structure unit, and "a"-"c" or "d"-"e" may be arranged in any sequential
order.
The above ether compounds, when used as a base oil for a working fluid
composition for a refrigerating machine, give the same effect as the
polyol ether derivatives represented by formula (XI), and, therefore,
these compounds can be used similarly in a working fluid composition for a
refrigerating machine. In such a case, the polyol ether derivatives
represented by formula (XIII.sub.AA) or (XIII.sub.BB) may be used alone or
as a mixture with the polyol ether derivatives represented by formula
(XI). When the polyol ether derivatives represented by formula
(XIII.sub.AA) or (XIII.sub.BB) are used alone, polyol ether acetals or
polyol ether ketals separated from a mixture of polyol ethers may be
alkylated, or the polyol ether derivatives represented by formula
(XIII.sub.AA) or (XIII.sub.BB) may be separated from the polyol ether
derivatives obtained after alkylation. The methods for separation and
alkylation are the same as those for the polyol ether derivatives
represented by formula (XI).
The alkyl, alcohol residue, and other groups of the polyol ether
derivatives represented by formulas (XIII.sub.AA) and (XIII.sub.BB) are
the same as those represented by formula (XI).
The thus-obtained polyol ether derivatives represented by formulas (XI) and
(XIII.sub.AA) or (XIII.sub.BB) may be used after purification to remove
by-products or unchanged compounds, or may be used without purification as
long as the presence of a small amount of by-products and unchanged
compounds does not impair the effects of the present invention. For
example, a portion of ketals or acetals (3-XVII) may remain
unhydrogenated, and un-capped hydroxyls may also remain.
The polyol ether derivatives represented by formulas (XI) and (XIII.sub.AA)
or (XIII.sub.BB) and used in the working fluid composition for a
refrigerating machine described above in "(3) A working fluid composition
for a refrigerating machine comprising a refrigeration oil containing as a
base oil polyol ether derivatives and a hydrofluorocarbon" are hereinafter
simply referred to as the ether compounds in the present invention) are
not particularly restricted in molecular weight. However, when they are
used as a refrigeration oil, the average molecular weight is preferably in
the range of from 200 to 800, more preferably 300 to 700 in view of better
sealing for the compressor, compatibility with hydrofluorocarbon, and
lubricity.
The viscosity of the ether compounds in the present invention at
100.degree. C. is preferably 0.5 to 30 mm.sup.2 /s, more preferably 1 to
15 mm.sup.2 /s. When the viscosity of the ether compounds in the present
invention at 100.degree. C. exceeds 30 mm.sup.2 /s, the compatibility with
hydrofluorocarbons becomes poor. The viscosity at 40.degree. C. of the
ether compounds in the present invention is preferably 1 to 300 mm.sup.2
/s, more preferably 5 to 100 mm.sup.2 /s. Among the ether compounds in the
present invention having a viscosity in the above ranges, preferable are
those of which phase separation temperature at low temperature is low.
Specifically, suitable examples are those having a critical solution
temperature of not higher than 10.degree. C., more preferably not higher
than 0.degree. C., further preferably not higher than -10.degree. C.
When used as a refrigeration oil for room air conditioners and
refrigerators, the ether compounds in the present invention are required
to have good insulating properties. Specifically, the volume resistivity
of the ether compounds in the present invention is normally not less than
10.sup.11 .OMEGA..multidot.cm, preferably not less than 10.sup.12
.OMEGA..multidot.cm, more preferably not less than 10.sup.13
.OMEGA..multidot.cm. In order to prevent the solidification of the
refrigeration oil at low temperatures, the pour point of the ether
compounds in the present invention is preferably not higher than
-10.degree. C., more preferably not higher than -20.degree. C.
The refrigeration oil containing the ether compounds in the present
invention as a base oil may be a mixture of the ether compounds in the
present invention with other synthetic oils, such as mineral oils, poly
a-olefins, alkyl benzenes, other ethers and polyethers, PAG, PAG-OH,
ketones, esters, perfluoropolyethers, and phosphates. The above-mentioned
ether compounds may be used singly or as a mixture of two or more kinds
for refrigeration oil containing as a base oil the ether compounds in the
present invention.
The ether compounds in the present invention may be used with or without
various additives.
For example, room air conditioners are commonly filled with a refrigerant
upon installation, and, therefore, there is a high risk of water
contamination. Although the ether compounds in the present invention are
chemically stable in the presence of water, the insulating materials, such
as PET film, may be hydrolyzed in the presence of water to yield PET
oligomers, which may result in plugged capillaries of refrigerating
machines. Therefore, it is preferred to use additives for removing water,
such as epoxy compounds having an epoxy group, orthoesters, acetals
(ketals), and carbodiimides.
The refrigeration oil comprising the ether compounds in the present
invention which further comprises one or more compounds selected from the
group consisting of (a) compounds having an epoxyl group, (b) orthoesters,
(c) acetals (ketals), and (d) carbodiimides allows to provide a further
improved refrigeration oil, and is an extremely preferable embodiment of
the refrigeration oil using as a base oil the ether compounds in the
present invention. Accordingly, a working fluid composition for a
refrigerating machine comprising such an improved refrigeration oil and a
hydrofluorocarbon is an extremely preferable embodiment of the working
fluid composition for a refrigerating machine of the present invention.
(a) Compounds having epoxy groups are those having 4-60 carbon atoms,
preferably those having 5-25 carbon atoms. Suitable examples include
glycidyl ethers, such as phenylglycidyl ether, butylglycidyl ether,
2-ethylhexylglycidyl ether, cresylglycidyl ether,
neopentylglycoldiglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol
triglycidyl ether, trimethylolpropane triglycidyl ether, and
pentaerythritol tetraglycidyl ether; glycidyl esters, such as diglycidyl
phthalate, diglycidyl cyclohexanedicarboxylate, diglycidyl adipate, and
glycidyl 2-ethylhexanoate; epoxidated monoesters of fatty acids, such as
methyl epoxystearate, and butyl epoxystearate; epoxidated vegetable oils,
such as epoxidated soybean oil and epoxidated linseed oil; and alicyclic
epoxy compounds, such as epoxycyclooctane, epoxycycloheptane and compounds
having an epoxycyclohexyl group and compounds having an epoxycyclopentyl
group exemplified below.
The compounds having an epoxycyclohexyl or an epoxycyclopentyl are those
having 5 to 40 carbon atoms, preferably 5-25 carbon atoms. Specifically,
those set forth in column 11, lines 34 to 46 of Japanese Patent Laid-open
No. 5-209171 are suitably used. Though they are not particularly limited,
a preference is given to 1,2-epoxycyclohexane, 1,2-epoxycyclopentane,
bis(3,4-epoxycyclohexylmethyl)adipate,
bis(3,4-epoxy-6-methylcyclohexylmethyl)adipate,
3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, and
2-(7-oxabicyclo›4.1.0!hept-3-yl)-spiro(1,3-dioxane-5,3'-›7!oxabicyclo›4.1.
0!heptane).
In the present invention, the above epoxy compounds may be used singly or
in combination of two or more kinds. The amount of the epoxy compound to
be added is usually 0.05 to 2.0 parts by weight, preferably 0.1 to 1.5
parts by weight, more preferably 0.1 to 1.0 parts by weight, based on 100
parts by weight of the ether compounds in the present invention used.
(b) The orthoesters used in the present invention are those having 4-70
carbon atoms, preferably those having 4-50 carbon atoms. Specifically,
orthoesters set forth in column 10, lines 7-41 of Japanese Patent
Laid-Open No. 6-17073 are suitably used. The amount of orthoesters to be
added is normally 0.01 to 100 parts by weight, preferably 0.05 to 30 parts
by weight, based upon 100 parts by weight of the ether compounds in the
present invention used.
(c) The acetals or ketals added in the present invention are those having
4-70 carbon atoms, preferably those having 4-50 carbon atoms.
Specifically, those set forth in column 10, line 47 to column 11, line 21
of Japanese Patent Laid-Open No. 6-17073 are suitably used. The amount of
acetals or ketals to be added is normally 0.01 to 100 parts by weight,
preferably 0.05 to 30 parts by weight, based upon 100 parts by weight of
the ether compounds in the present invention used.
(d) Carbodiimides used in the present invention is represented by the
following formula:
R.sub.10 --N.dbd.C.dbd.N--R.sub.11
wherein R.sub.10 and R.sub.11 represent a hydrocarbon group having 1-20
carbon atoms, preferably 1-12 carbon atoms; and R.sub.10 and R.sub.11 may
be identical or different.
Examples of R.sub.10 and R.sub.11 include alkyl groups, such as methyl,
ethyl, propyl, isopropyl, cyclopropyl, butyl, 1-methylpropyl,
2-methylpropyl, t-butyl, pentyl, 1-methylbutyl, 2-methylbutyl,
3-methylbutyl, 1-ethylpropyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl,
2,2-dimethylpropyl, cyclopentyl, hexyl, 1-methylpentyl, 2-methylpentyl,
3-methylpentyl, 4-methylpentyl, 1-ethylbutyl, 2-ethylbutyl,
1,1-dimethylbutyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl,
2,2-dimethylbutyl, 2,3-dimethylbutyl, 3,3-dimethylbutyl,
1-ethyl-2-methylpropyl, 1-ethyl-1-methylpropyl, 1,1,2-trimethylpropyl,
1,2,2-trimethylpropyl, cyclohexyl, cyclopentylmethyl, methylcyclopentyl,
heptyl, 1-methylhexyl, 2-methylhexyl, 3-methylhexyl, 4-methylhexyl,
5-methylhexyl, 1-ethylpentyl, 2-ethylpentyl, 2,4-dimethylpentyl,
3,4-dimethylpentyl, 1,1-dimethylpentyl, 1,4-dimethylpentyl, 1-propylbutyl,
1-isopropylbutyl, 1,3,3-trimethylbutyl, 1,1-diethylpropyl,
2,2-dimethyl-1-ethylpropyl, 1,2-dimethyl-1-ethylpropyl,
1-isopropyl-2-methylpropyl, cycloheptyl, cyclohexylmethyl,
methylcyclohexyl, octyl, 1-methylheptyl, 2-methylheptyl, 1-ethylhexyl,
2-ethylhexyl, 1,1,3,3-tetramethylbutyl, 1,1-diisopropylethyl,
1-ethyl-1,2,2-trimethylpropyl, 1,5-dimethylhexyl, 3,5-dimethylhexyl,
2-propylpentyl, 2,4,4-trimethylpentyl, 1-ethyl-2-methylpentyl,
2,2-dimethylhexyl, 1,1-dimethylhexyl, cycloheptylmethyl,
dimethylcyclohexyl, 4-methylcyclohexylmethyl, cycloheptylmethyl,
cyclooctyl, 1-cyclohexylethyl, 2-cyclohexylethyl, ethylcyclohexyl, nonyl,
1-methyloctyl, 5-methyloctyl, 1-(2'-methylpropyl)-3-methylbutyl,
3,5,5-trimethylhexyl, 1,1-diethyl-2,2-dimethylpropyl, 3-cyclohexylpropyl,
1,1-dimethylheptyl, decyl, 1-methylnonyl, 1-propylheptyl,
3,7-dimethyloctyl, 2,4,6-trimethylheptyl, 4-cyclohexylbutyl,
butylcyclohexyl, 3,3,5,5-tetramethylcyclohexyl, undecyl, 1-methyldecyl,
2-methyldecyl, 2-ethylnonyl, dodecyl, 1-methylundecyl, 2-methylundecyl,
2-ethyldecyl, 1-(2'-methylpropyl)-3,5-dimethylhexyl, tridecyl,
2,4,6,8-tetramethylnonyl, 2-methyldodecyl, 2-ethylundecyl,
1-(3'-methylbutyl)-6-methylheptyl, 1-(1'-methylbutyl)-4-methylheptyl,
tetradecyl, 1-methyltridecyl, 2-methyltridecyl, 2-ethyldodecyl,
2-(3'-methylbutyl)-7-methyloctyl, 2-(1'-methylbutyl)-5-methyloctyl,
pentadecyl, 1-hexylnonyl, 2-methyltetradecyl, 2-ethyltridecyl, hexadecyl,
1-methylpentadecyl, 2-hexyldecyl, heptadecyl, 1-heptyldecyl,
1-(1',3',3'-trimethylbutyl)-4,6,6-trimethylheptyl,
1-(3'-methylhexyl)-6-methylnonyl, octadecyl, 2-heptylundecyl,
2-(1',3',3'-trimethylbutyl)-5,7,7-trimethyloctyl,
2-(3'-methylhexyl)-7-methyldecyl, and 2-octyldodecyl; aryl and alkyl aryl
groups, such as phenyl, 2-, 3-, or 4-methylphenyl, 2-, 3-, or
4-ethylphenyl, 2,3-, 2,4-, 2,5-, 2,6-, 3,4-, or 3,5-dimethylphenyl, 2-,
3-, or 4-isopropylphenyl, 2-, 3-, or 4-propylphenyl, 2,3,5-, 2,3,6-2,4,6-,
or 3,4,5-trimethylphenyl, 2-, 3-, or 4-tert-butylphenyl, 2-, 3-, or
4-sec-butylphenyl, 4- or 5-isopropyl-3-methylphenyl, 4-tert-amylphenyl,
3-, 4-, or 5-methyl-2-tert-butylphenyl, pentamethylphenyl, naphthyl,
2-methylnaphthyl, 2,6-diisopropylphenyl, 4-tert-octylphenyl, 2,4-, 2,6-,
or 3,5-di-tert-butylphenyl, di-sec-butylphenyl,
2,6,-di-tert-butyl-4-methylphenyl, and 2,4,6-tri-tert-butylphenyl; and
aralkyl groups, such as benzyl, 2-, 3-, or 4-methylbenzyl, phenetyl,
sec-phenetyl, 2,4-, 2,5-, 3,4- or 3,5-dimethylbenzyl, 4-ethylbenzyl, 2-,
3-, or 4-methylphenetyl, .alpha.- or .beta.-methylphenetyl,
.alpha.,.alpha.-dimethylbenzyl, 1- or 3-phenylpropyl, .alpha.- or
.beta.-ethylphenetyl, 4-isopropylbenzyl, .alpha.-isopropylbenzyl,
.alpha.,.alpha.-dimethylphenetyl, 1-, 3-, or 4-phenylbutyl,
.alpha.-ethyl-.alpha.-methylbenzyl, 4-butylbenzyl, 4-tert-butylbenzyl,
1,1-dimethyl-3-phenylpropyl, 1- or 3-phenyl-2,2-dimethylpropyl,
a-propylphenetyl, 5-phenylpentyl, naphthylmethyl, naphthylethyl, and
6-phenylhexyl.
Examples of the carbodiimides include 1,3-diisopropylcarbodiimide,
1,3-di-tert-butylcarbodiimide, 1,3-dicyclohexylcarbodiimide,
1,3-di-p-tolylcarbodiimide, and 1,3-(2,6-diisopropylphenyl)carbodiimide,
with a preference given to 1,3-dicyclohexylcarbodiimide,
1,3-di-p-tolylcarbodiimide, and
1,3-bis-(2,6-diisopropylphenyl)carbodiimide.
The amount of the carbodiimide added in the present invention is normally
0.01 to 10 parts by weight, preferably 0.05 to 5 parts by weight, based
upon 100 parts by weight of the ether compounds in the present invention.
In addition to the above additive to remove water, the following additives
may be added: lubricity additives, such as triaryl phosphate and/or
triaryl phosphite; radical trapping additives, such as phenol compounds or
metal deactivators having chelating capacity for improving thermal
stability; and metal surface protective agents, such as benzotriazol
and/or benzotriazol derivatives.
Triaryl phosphates and triaryl phosphites used in the present invention are
those having 18-70 carbon atoms, preferably 18-50 carbon atoms. Examples
of the triaryl phosphates and triaryl phosphites used in the present
invention are set forth in Japanese Patent Laid-Open No. 5-209171, column
12, lines 26 to 41. Among the examples, the following compounds are
particularly preferable: triphenyl phosphate, tricresyl phosphate,
trixylenyl phosphate, tris(2,4-di-tert-butylphenyl)phosphate, triphenyl
phophite, tricresyl phosphite, trixylenyl phosphite, and
tris(2,4-di-tert-butylphenyl)phosphite.
The amount of triaryl phosphates and triaryl phosphites added in the
present invention is normally 0.1 to 5.0 parts by weight, preferably 0.5
to 2.0 parts by weight, based upon 100 parts by weight of the ether
compounds in the present invention.
Phenol compounds having a radical trapping capacity are those having 6-100
carbon atoms, preferably 10-80 carbon atoms. Examples of the phenol
compounds are set forth in Japanese Patent Laid-Open No. 5-209171, column
12, line 32 to column 13, line 18. Of the examples, the following
compounds are particularly preferable: 2,6-di-tert-butylphenol,
2,6-di-tert-butyl-4-methylphenol,
4,4'-methylenebis(2,6-di-tert-butylphenol),
4,4'-butylidenebis(3-methyl-6-tert-butylphenol),
2,2'-methylenebis(4-ethyl-6-tert-butylphenol),
2,2'-methylenebis(4-methyl-6-tert-butylphenol),
4,4'-isopropylidenebisphenol, 2,4-dimethyl-6-tert-butylphenol,
tetrakis›methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate!methane
, 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane,
1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene,
2,6-di-tert-butyl-4-ethylphenol,
2,6-bis(2'-hydroxy-3'-tert-butyl-5'-methylbenzyl)-4-methylphenol,
bis›2-(2-hydroxy-5-methyl-3-tert-butylbenzyl)-4-methyl-6-tert-butylphenyl!
terephthalate,
triethyleneglycol-bis›3-(3,5-di-tert-butyl-5-methyl-4-hydroxyphenyl)propio
nate!, and
1,6-hexanediol-bis›3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate!.
The amount of the phenol compounds added in the present invention is
normally 0.05 to 2.0 parts by weight, preferably 0.05 to 0.5 parts by
weight, based upon 100 parts by weight of the ether compounds in the
present invention.
The metal deactivators used in the present invention is preferably those
with a chelating capacity, and having 5-50 carbon atoms, preferably 5-20
carbon atoms. Examples of the metal deactivators are set forth in Japanese
Patent Laid Open No. 5-209171, column 13, line 38 to column 14, line 8. Of
the examples, the following compounds are particularly preferable:
N,N'-disalicylidene-1,2-diaminoethane,
N,N'-disalicylidene-1,2-diaminopropane, acetylacetone, acetoacetate,
alizarine, and quinizarin.
The amount of the metal deactivators added in the present invention is
normally 0.001 to 2.0 parts by weight, preferably 0.003 to 0.5 parts by
weight, based upon 100 parts by weight of the ether compounds in the
present invention.
The benzotriazol and benzotriazol derivatives used in the present invention
is preferably those having 6-50 carbon atoms, more preferably 6-30 carbon
atoms. Examples of the benzotriazol and benzotriazol derivatives are set
forth in Japanese Patent Laid Open No. 5-209171, column 13, lines 9 to 29.
Of the examples, benzotriazol and 5-methyl-1H-benzotriazol are
particularly preferable.
The amount of benzotriazol and/or benzotriazol derivatives added in the
present invention is normally 0.001 to 0.1 parts by weight, preferably
0.003 to 0.03 parts by weight, based upon 100 parts by weight of the ether
compounds in the present invention.
Other additives conventionally used for lubricating oil, such as
antioxidants, extreme pressure additives, oiliness improvers, and
defoaming agents, may be added according to necessity. For examples,
antioxidants usable in the present invention are amine-based antioxidants,
such as p,p-dioctylphenylamine, monooctyldiphenylamine, phenothiazine,
3,7-dioctylphenothiazine, phenyl-1-naphthylamine, phenyl-2-naphthylamine,
alkylphenyl-1-naphthylamine, and alkylphenyl-2-naphthylamine; sulfur-based
antioxidants, such as alkyl disulfides, thiodipropionic acid esters, and
benzothiazoles; and zinc compounds, such as zinc dialkyl dithiophosphate
and zinc diaryl dithiophosphate. The amounts of the above additives are
0.05 to 2.0 parts by weight, based on 100 parts by weight of the ether
compounds in the present invention.
Examples of the extreme-pressure additives and oiliness agents usable in
the present invention are zinc compounds, such as zinc dialkyl
dithiophosphate and zinc diaryl dithiophosphate; sulfur compounds, such as
thiodipropionic acid esters, dialkyl sulfide, dibenzyl sulfide, dialkyl
polysulfide, alkyl mercaptan, dibenzothiophene, and
2,2'-dithiobis(benzothiazole): phosphorus compounds, such as trialkyl
phosphite, and trialkyl phosphate; chlorine compounds, such as chlorinated
paraffin; molybdenum compounds, such as molybdenum dithiocarbamate,
molybdenum dithiophosphate, and molybdenum disulfide; fluorine compounds,
such as perfluoroalkyl polyethers, trifluorochloro ethylene polymers,
graphitefluoride; silica compounds, such as fatty acid-modified silicone;
and graphite. The amount added in the present invention is 0.05 to 10
parts by weight, based upon 100 parts by weight of the ether compound of
the present invention.
Examples of defoaming agents usable in the present invention are silicone
oils, such as dimethylpolysiloxane; and organosilicates, such as diethyl
silicate. The amount added in the present invention is 0.0005 to 1 parts
by weight, based on 100 parts by weight of the ether compound of the
present invention.
Additives stabilizing freon refrigerants, such as organic tin compounds and
boron compounds, may be added in the present invention. The amount added
in the present invention is 0.001 to 10 parts by weight, based on 100
parts by weight of the ether compounds in the present invention.
The mixing ratio of a hydrofluorocarbon with a refrigeration oil containing
the ether compounds in the present invention as a base oil or with a
refrigeration oil containing the above base oil to which additives are
further added (hydrofluorocarbon/oil) is normally 50/1 to 1/20 (weight
ratio), preferably 10/1 to 1/5 (weight ratio). When the mixing ratio
exceeds 50/1, the viscosity of the mixed solution of hydrofluorocarbon and
oil becomes low, thereby making it likely to have undesirably poor
lubricity. When the mixing ratio is lower than 1/20, the refrigeration
ability is likely to become undesirably poor.
The hydrofluorocarbons used in the present invention include
difluoromethane (HFC32), 1,1-difluoroethane (HFC152a),
1,1,1-trifluoroethane (HFC143a), 1,1,1,2-tetrafluoroethane (HFC134a),
1,1,2,2-tetrafluoroethane (HFC134) and pentafluoroethane (HFC125), with a
particular preference given to 1,1,1,2-tetrafluoroethane,
pentafluoroethane, and difluoromethane.
EXAMPLES
The present invention will be further described by means of Examples,
without intending to restrict the scope of the present invention thereto.
Example 1-1
Synthesis of 1,6-di-O-(3,5,5-trimethylhexyl)sorbitol ›Compound (1b)!
1) 1.2:3.4:5.6-tri-O-(3,5,5-trimethylhexylidene)sorbitol: Compound (1a)
In a 3-liter reaction vessel equipped with a thermometer, a reflux
condenser, a Dean and Stark trap, a calcium chloride tube, and a stirrer,
170.76 g (0.937 mol) of D-sorbitol, 400 g (2.812 mol) of
3,5,5-trimethylhexanal, 1.78 g (0.00936 mol) of p-toluene sulfonic acid 1
hydrate, and 400 ml of hexane were placed and heated with stirring. A
reaction was carried out at a temperature of from 79.degree. to 81.degree.
C. for 8 hours while distilling off a theoretical amount of water. After
being cooled to 70.degree. C., the reaction mixture was neutralized by
adding 1.99 g (0.0188 mol) of sodium carbonate, and stirred at 70.degree.
C. for 30 minutes. After 100 g of water was added to the mixture and
stirred at 60.degree. C. for 30 minutes, the mixture was allowed to stand
to separate into two layers. After the lower layer was discarded, the
remaining mixture was washed with 100 g of saturated brine, and evaporated
to give 529.51 g of crude Compound (1a).
The obtained product was subjected to a reduced-pressure distillation and a
forerun was discarded. 500.87 g of the residue was dissolved in 500 ml of
hexane. The hexane solution was subjected to an adsorption treatment by
passing through 25.04 g (5% by weight to the residue) of activated clay on
a filter (PTFE, 0.2 .mu.m) under pressure. After washing the clay cake
with hexane, the hexane in the solution was completely distilled away to
give 501.14 g of Compound (1a) (yield: 96.4%).
The product has a purity of 96.3% as determined by gas chromatography, and
a hydroxyl value of 27.2. (theoretical value of 0).
2) 1,6-di-O-(3,5,5-trimethylhexyl)sorbitol: Compound (1b)
In a 1-liter autoclave, 487.1 g (0.878 mol) of the obtained Compound (1a),
and 9.74 g (2% by weight) of 5% Pd/C catalyst were placed, the 5% Pd/C
catalyst being prepared by drying a commercially available product with
50% moisture content (5% Pd carbon powder with 50% moisture content,
E-type, pH 6.0, manufactured by N. E. Chemcat Corp.) at room temperature
for one day under reduced pressure using a vacuum pump. The temperature of
the autoclave was raised with stirring the mixture under a hydrogen
pressure of 20 kg/cm.sup.2. Then the mixture was kept for 8 hours under a
hydrogen pressure of 200 kg/cm.sup.2 at 190.degree. C. The hydroxyl value
at the completion of the reaction was 243.3 ›theoretical value: 300.9 (as
an ether alcohol with an average alkyl substituent number of 3.0)!. The
reaction mixture was dissolved in 300 ml of isopropanol, and the mixture
was subjected to a pressure-filtration through a membrane filter (PTFE,
0.2 .mu.m). The filtrate was evaporated to give 475.85 g of a crude
mixture of polyol ethers (yield of crude mixture: 96.6%). The composition
of the mixture determined by gas chromatography was as follows: 19% of
dialkyl product; 47% of trialkyl product; 18% of tetraalkyl product; 3% of
monoalkyl product; and 2% of pentaalkyl product. 200 g of the crude
mixture was weighed and subjected to a silica gel column chromatography
for purification, in which 18.2 g of purified Compound (1b) was obtained
by elution with hexane/ethanol ›93/7 (vol/vol)! after elution of Compound
(3) with hexane/ethanol ›97/3 (vol/vol)! and elution of Compound (2) with
hexane/ethanol ›95/5 (vol/vol)!. The purity of Compound (1b) was
determined to be 90.5% by gas chromatography, and the hydroxyl value of
the compound was 471 (theoretical value: 517).
IR (NEAT, cm.sup.-1): 3465 (O-H stretching), 2954 (C-H stretching), 1473,
1395, 1368 (C-H deformation), 1122 (C-O stretching)
.sup.1 H NMR (CDCl.sub.3, .delta.ppm): 0.77-1.35 (28H, multiplet,
--CH(CH.sub.3)CH.sub.2 C(CH.sub.3).sub.3) 1.35-1.75 (2H, multiplet,
--CH.sub.2 CH(CH.sub.3)CH.sub.2 C(CH.sub.3).sub.3) 3.03 (4H, singlet,
--OH) 3.43-4.02 (12H, multiplet, --CH(OH)--, --CH.sub.2 OCH.sub.2 --)
MASS (FD): 436 (M+1)
Example 1-2
Synthesis of 1,3,6-tri-O-(3,5,5-trimethylhexyl)sorbitol ›Compound (2)!
100 g of the crude mixture of polyol ethers obtained in Example 1-1 was
purified similarly to Example 1-1 by silica gel column chromatography.
That is, after Compound (3) was eluted with hexane/ethanol ›97/3
(vol/vol)!, Compound (2) was eluted using a hexane/ethanol ›95/5
(vol/vol)! developing solvent. As a result, 32.3 g of Compound (2) was
obtained. The purity of Compound (2) was determined to be 93.3% by gas
chromatography, and the hydroxyl value of the compound was 280
(theoretical value: 301).
IR (NEAT, cm.sup.-1): 3466 (O-H stretching), 2956 (C-H stretching), 1473,
1395, 1368 (C-H deformation), 1122 (C-O stretching)
.sup.1 H NMR (CDCl.sub.3, .delta.ppm): 0.77-1.35 (42H, multiplet,
--CH(CH.sub.3)CH.sub.2 C(CH.sub.3).sub.3) 1.35-1.80 (9H, multiplet,
--CH.sub.2 CH(CH.sub.3)CH.sub.2 C(CH.sub.3).sub.3) 3.40-4.00 (14H,
multiplet, --CH(OH)--, --CH.sub.2 OCH.sub.2 --)
MASS (FD): 688 (M+1)
Example 1-3
Synthesis of 1,3,6,x-tetra-O-(3,5,5-trimethylhexyl)sorbitol ›Compound (3)!
(x represents a figure of 2, 4 or 5; x in the Examples below has the same
definition)
100 g of the crude mixture of polyol ethers obtained in Example 1-1 was
purified similarly to Example 1-1 by silica gel column chromatography
using a hexane/ethanol ›97/3 (vol/vol)! developing solvent to give 24.0 g
of Compound (3). The purity of Compound (3) was determined to be 83.5% by
gas chromatography, and the hydroxyl value of the compound was 174
(theoretical value: 163).
IR (NEAT, cm.sup.-1): 3465 (O-H stretching), 2954 (C-H stretching), 1473,
1394, 1367 (C-H deformation), 1120 (C-O stretching)
MASS (FD): 351 (M+1)
Example 1-4
Synthesis of a mixture of 1-O-(3,5,5-trimethylhexyl)sorbitol,
1,6-di-O-(3,5,5-trimethylhexyl)sorbitol,
1,3,6-tri-O-(3,5,5-trimethylhexyl)sorbitol,
1,3,6x-tetra-O-(3,5,5-trimethylhexyl)sorbitol, and
1,3,6,x,y-penta-O-(3,5,5-trimethylhexyl)sorbitol (ether alcohols having an
average alkyl substituent number of 3.1) ›Compounds (4)!
(y represents a figure of 2, 4, or 5, the figure being different from x; y
in the Examples below has the same definition)
200 g of the crude mixture of polyol ethers obtained in Example 1-1 was
purified by heating under a reduced pressure (192.degree. C. at 0.6 mmHg)
to remove low-boiling point components. As a result, 178 g of Compounds
(4) was obtained (yield: 89.2%). The composition of the obtained Compounds
(4) as determined by gas chromatography was as follows: 3% of monoalkyl
product; 21% of dialkyl product; 53% of trialkyl product; 20% of
tetraalkyl product; and 2% of pentaalkyl product. The hydroxyl value of
the mixture was 282 (ether alcohols with an average alkyl substituent
number of 3.1).
IR (NEAT, cm.sup.-1): 3466 (O-H stretching), 2955 (C-H stretching), 1473,
1395, 1367 (C-H deformation), 1118 (C-O stretching)
Example 1-5
Synthesis of a mixture of 1-mono-O-(3,5,5-trimethylhexyl)sorbitol,
1,6-di-O-(3,5,5-trimethylhexyl)sorbitol,
1,3,6-tri-O-(3,5,5-trimethylhexyl)sorbitol,
1,3,6,x-tetra-O-(3,5,5-trimethylhexyl)sorbitol, and
1,3,6,x,y-penta-O-(3,5,5-trimethylhexyl)sorbitol, (ether alcohols having
an average alkyl substituent number of 2.0) ›Compounds (5)!
In a 1-liter autoclave, 480 g (0.865 mol) of
1.2:3.4:5.6-tri-O-(3,5,5-trimethylhexylidene)sorbitol (1a), 78.8 g (0.433
mol) of D-sorbitol, and 9.74 g (2% by weight) of 5% Pd/C catalyst were
placed, the 5% Pd/C catalyst being prepared by drying a commercially
available product with 50% moisture content (5% Pd carbon powder with 50%
moisture content, E-type, pH 6.0, manufactured by N. E. Chemcat Corp.) at
room temperature for one day under a reduced pressure using a vacuum pump.
The temperature of the autoclave was raised with stirring the mixture
under a hydrogen pressure of 20 kg/cm.sup.2. Then the mixture was kept for
25 hours under a hydrogen pressure of 200 kg/cm.sup.2 at 190.degree. C.
The reaction mixture was dissolved in 300 ml of isopropanol, and subjected
to a pressure-filtration through a membrane filter (PTFE, 0.2 .mu.m). The
filtrate was evaporated to give 532.0 g of a crude mixture of polyol
ethers (yield of crude mixture: 95.1%).
The crude mixture of polyol ethers obtained was purified by heating under a
reduced pressure (182.degree.-207.degree. C. at 0.6 mmHg) to remove
low-boiling point components. As a result, 484 g of Compounds (5) was
obtained (yield: 91.0%).
The composition of the obtained Compounds (5) as determined by gas
chromatography was as follows: 34% of monoalkyl product; 47% of dialkyl
product; 16% of trialkyl product; and 1% of tetraalkyl product. The
hydroxyl value of the mixture was 521 (ether alcohols with an average
alkyl substituent number of 2.0).
Example 1-6
Synthesis of 2,3,4,5-tetra-O-methyl-1,6-di-O-(3,5,5-trimethylhexyl)sorbitol
›Compound (6)!
In a 1-liter reaction vessel equipped with a thermometer, a reflux
condenser, a dropping funnel, and a stirrer, 7.3 g (0.18 mol) of sodium
hydride (content: 60%, oily) was placed. The sodium hydride was washed
with 50 ml of hexane by decantation. Then, 320 ml of a mixed solvent of
1,2-dimethoxyethane/dimethylsulfoxide (3/1, vol/vol) was added to the
vessel. Then, 17.0 g (0.039 mol) of Compound (1b) obtained in Example 1-1
was dissolved in 16 ml of the mixed solvent and added dropwise to the
vessel with stirring over 10 minutes at room temperature. The reaction
mixture was heated to 50.degree. C., and stirred for 1 hours with
maintaining the temperature. After the mixture was cooled to 40.degree.
C., 22.9 g (0.18 mol) of dimethyl sulfate was added dropwise over 20
minutes with the temperature maintained below 50.degree. C. After the
mixture was stirred for another 1 hour at 50.degree. C. and cooled, 72.0 g
(0.18 mol) of 10% aqueous solution of sodium hydroxide was added. Then the
mixture was stirred at 70.degree. to 80.degree. C. for 1 hour. After
cooling, 100 ml of water was added to allow phase separation. The aqueous
layer was extracted twice with 150 ml of diethyl ether, and the organic
layer was combined with the ether extracts. The mixture was washed three
times with 100 ml of saturated brine and dried over anhydrous sodium
sulfate. Then, the solvent was distilled away with an evaporator to give
21.2 g of oily substance. This substance was purified by silica gel column
chromatography using a hexane/diethyl ether ›90/10 (vol/vol)! developing
solvent and subjected to a reduced-pressure distillation (boiling point:
179.degree. C. at 0.35 mmHg) to give 6.8 g of Compound (6). The purity of
Compound (6) was determined to be 99.7% by gas chromatography.
IR (NEAT, cm.sup.-1): 2950 (C-H stretching), 1473, 1368 (C-H deformation),
1116 (C-O stretching)
.sup.1 H NMR (CDCl.sub.3, .delta.ppm): 0.80-1.33 (28H, multiplet,
--CH(CH.sub.3)CH.sub.2 C(CH.sub.3).sub.3) 1.33-1.80 (6H, multiplet,
--CH.sub.2 CH(CH.sub.3)CH.sub.2 C(CH.sub.3).sub.3) 3.35-3.80 (24H,
multiplet, --CH(OCH.sub.3)--, --CH.sub.2 OCH.sub.2 --)
Example 1-7
Synthesis of 2,4,5-tri-O-methyl-1,3,6-tri-O-(3,5,5-trimethylhexyl)sorbitol
›Compound (7)!
In a 1-liter reaction vessel equipped with a thermometer, a reflux
condenser, a dropping funnel, and a stirrer, 4.9 g (0.12 mol) of sodium
hydride (content: 60%, oily) was placed. The sodium hydride was washed
with 50 ml of hexane by decantation. Then, 320 ml of a mixed solvent of
1,2-dimethoxyethane/dimethylsulfoxide (3/1, vol/vol) was added to the
vessel. 15.3 g (0.027 mol) of Compound (2) obtained in Example 1-2 was
dissolved in 12 ml of the mixed solvent and added dropwise to the vessel
with stirring over 10 minutes at room temperature. The reaction mixture
was heated to 50.degree. C. and stirred for 30 minutes with maintaining
the temperature. After the mixture was cooled to 40.degree. C., 15.5 g
(0.12 mol) of dimethyl sulfate was added dropwise over 1 hour with the
temperature maintained below 50.degree. C. After the mixture was stirred
for another 1 hour at 50.degree. C. and cooled, 48.0 g (0.12 mol) of 10%
aqueous solution of sodium hydroxide was added. Then the mixture was
stirred at 70.degree. to 80.degree. C. for 1 hour. After cooling, the
mixture was allowed to phase separate. The aqueous layer was extracted
twice with 100 ml of diethyl ether, and then the organic layer was
combined with the ether extracts. The mixture was washed three times with
50 ml of saturated brine and dried over anhydrous sodium sulfate. Then,
the solvent was distilled away with an evaporator to give 16.9 g of oily
substance. This substance was purified by silica gel column chromatography
using a hexane/diethyl ether ›90/10 (vol/vol)! developing solvent to give
12.6 g of Compound (7). The purity of Compound (7) was determined to be
98.4% by gas chromatography.
IR (NEAT, cm.sup.-1): 2956 (C-H stretching), 1470, 1368 (C-H deformation),
1194 (C-O stretching)
.sup.1 H NMR (CDCl.sub.3, .delta.ppm): 0.78-1.10 (42H, multiplet,
--CH(CH.sub.3)CH.sub.2 C(CH.sub.3).sub.3) 1.16-1.78 (9H, multiplet,
--CH.sub.2 CH(CH.sub.3)CH.sub.2 C(CH.sub.3).sub.3) 3.23-3.85 (23H,
multiplet, --CH(OCH.sub.3)--, --CH.sub.2 OCH.sub.2 --)
Example 1-8-1
Synthesis of a mixture of
2,3,4,5,6-penta-O-methyl-1-O-(3,5,5-trimethylhexyl)sorbitol,
2,3,4,5-tetra-O-methyl-1,6-di-O-(3,5,5-trimethylhexyl)sorbitol,
2,4,5-tri-O-methyl-1,3,6-tri-O-(3,5,5-trimethylhexyl)sorbitol,
di-O-methyl-1,3,6,x-tetra-O-(3,5,5-trimethylhexyl)sorbitol, and
O-methyl-1,3,6,x,y-penta-O-(3,5,5-trimethylhexyl)sorbitol methyl-capped
ether alcohols having an average alkyl substituent number of 2.0)
›Compounds (8-1)!
In a 3-liter reaction vessel equipped with a thermometer, a reflux
condenser, a dropping funnel, and a stirrer, 117 g (3.06 mol) of sodium
hydride (content: 60%, oily) was placed. The sodium hydride was washed
with 400 ml of hexane by decantation. Then, 1.5 liters of toluene was
added to the vessel.
220 g of Compounds (5) obtained in the same way as in Example 1-5 (ether
alcohol with hydroxyl value of 521 and average alkyl substituent number of
2.0), i.e., a mixture of mono-, di-, tri-, tetra-, and
penta-O-(3,5,5-trimethylhexyl)sorbitol, was dissolved in 300 ml of
toluene, and added dropwise to the vessel over 30 minutes at 24.degree. to
36.degree. C. The reaction mixture was heated to 90.degree. to 97.degree.
C. and stirred for 30 minutes with maintaining the temperature. After the
mixture was cooled to 40.degree. C., 386 g (3.06 mol) of dimethyl sulfate
was added dropwise over 2.5 hours with the temperature maintained below
60.degree. C. After the mixture was stirred for another 1 hour at
60.degree. C. and cooled, 898 g (3.37 mol) of 15% aqueous solution of
sodium hydroxide was added. Then the mixture was stirred at 80.degree. C.
for 1 hour. After cooling, the mixture was allowed to phase separate. The
water layer was extracted once with 300 ml of toluene, and the organic
layer was combined with the toluene. The mixture was washed three times
with 40 ml of saturated brine. Then, the mixture was dried over anhydrous
sodium sulfate, and the solvent was distilled away with an evaporator to
give 248 g of oily substance. The substance was purified by heating at
185.degree. to 190.degree. C. under a reduced pressure (0.7 mmHg) for 30
minutes to remove low-boiling point components. As a result 226 g of
Compounds (8-1) was obtained. The composition of the obtained Compounds
(8-1) as determined by gas chromatography was as follows: 34% of monoalkyl
product; 47% of dialkyl product; 16% of trialkyl product; and 1% of
tetraalkyl product.
IR (NEAT, cm.sup.-1): 2956 (C-H stretching), 1473, 1368 (C-H deformation),
1104 (C-O stretching)
Example 1-8-2
Synthesis of a mixture of
2,3,4,5-tetra-O-methyl-1,6-di-O-(3,5,5-trimethylhexyl)sorbitol,
2,4,5-tri-O-methyl-1,3,6-tri-O-(3,5,5-trimethylhexyl)sorbitol,
di-O-methyl-1,3,6,x-tetra-O-(3,5,5-trimethylhexyl)sorbitol, and
2,3,4,5,6-penta-O-methyl-1-O-(3,5,5-trimethylhexyl)sorbitol (methyl-capped
ether alcohols having an average alkyl substituent number of 3.1)
›Compounds (8-2)!
In a 2-liter reaction vessel equipped with a thermometer, a reflux
condenser, a dropping funnel, and a stirrer, 25.35 g (1.06 mol) of sodium
hydride powder and 500 ml of toluene were placed. 100 g (0.2 mol) of
Compounds (4) obtained in the same way as in Example 1-4, i.e., a mixture
of mono-, di-, tri-, and tetra-O-(3,5,5-trimethylhexyl)sorbitol, was
dissolved in 100 ml of toluene, and added dropwise to the vessel over 30
minutes with stirring at room temperature under nitrogen atmosphere. Then,
200 ml of toluene was added to the vessel. The reaction mixture was heated
to 110.degree. C. and refluxed with stirring for 30 minutes at 110.degree.
C. After the mixture was cooled to 50.degree. C., 133.22 g (1.06 mol) of
dimethyl sulfate was added dropwise over 1 hour with the temperature
maintained below 50.degree. C. 600 ml of toluene was further added and the
mixture was matured for 1 hour at 80.degree. C. After the mixture was
cooled and 422.5 g of 10% aqueous solution (1.06 mol) of sodium hydroxide
was added, the mixture was stirred at 70.degree. to 80.degree. C. for 30
minutes. After being cooled to room temperature, the mixture was allowed
to phase separate. The lower layer was discarded. The upper layer was
washed four times with 200 ml of saturated brine. Then, the mixture was
dried over anhydrous sodium sulfate, and subjected to adsorption treatment
with 2.2 g of activated carbon (2% by weight of activated carbon based on
the theoretical yield). After filtration, toluene in the filtrate was
distilled away to give oily substance. The oily substance was further
heated under a reduced pressure of 0.7 mmHg and the forerun was discarded
until the internal temperature reached 200.degree. C. As a result, 70.4 g
of Compounds (8-2) was obtained (yield: 64.4%).
The purity of the Compounds (8-2) was determined to be 96.1% by gas
chromatography.
The composition of the mixture was as follows: 3.5% by weight of
2,3,4,5,6-penta-O-methyl-1-O-(3,5,5-trimethylhexyl)sorbitol; 37.6% by
weight of 2,3,4,5-tetra-O-methyl-1,6-di-O-(3,5,5-trimethylhexyl)sorbitol;
42.9% by weight of
2,4,5-tri-O-methyl-1,3,6-tri-O-(3,5,5-trimethylhexyl)sorbitol; and 12.1%
by weight of di-O-methyl-1,3,6,x-tetra-O-(3,5,5-trimethylhexyl)sorbitol.
Example 1-9
Synthesis of 16-di-O-(1-methylpropyl)-O-(1-methylpropylidene)sorbitol
›Compound (9b)!
1) 1.2:3.4:5.6-tri-O-(1-methylpropylidene)sorbitol: Compound (9a)
In a 3-liter reaction vessel equipped with a thermometer, a reflux
condenser, a Dean and Stark trap, a calcium chloride tube, and a stirrer,
336.84 g (1.849 mol) of D-sorbitol, 800 g (11.094 mol) of methyl ethyl
ketone, 17.58 g (0.092 mol) of p-toluene sulfonic acid 1 hydrate, and 200
ml of hexane were placed and heated with stirring. A reaction was carried
out at a temperature of from 69.degree. to 79.degree. C. for 8 hours while
distilling off a theoretical amount of water. After being cooled to
60.degree. C., the reaction mixture was neutralized by adding 19.60 g
(0.185 mol) of sodium carbonate, and stirred at 60.degree. C. for 30
minutes. After 200 g of water was added to the mixture and stirred at for
60.degree. C. for 30 minutes, the mixture was allowed to stand to separate
into two layers. After the lower layer was discarded, the remaining
mixture was washed with 200 g of saturated brine, and evaporated to give
643.75 g of crude Compound (9a). The crude compound was subjected to a
reduced-pressure distillation to give 606.71 g of Compound (9a) (yield:
95.3%). The obtained Compound (9a) had a boiling point of 136.degree. to
140.degree. C. at 0.6 mmHg, purity as determined by gas chromatography of
97.3%, and a hydroxyl value of 12.9 (theoretical value: 0).
2) 1,6-di-O-(1-methylpropyl)-O-(1-methylpropylidene)sorbitol: Compound (9b)
In a 1-liter autoclave, 571.5 g (1.659 mol) of Compound (9a) obtained
above, and 11.43 g (2% by weight) of 5% Pd/C catalyst were placed, the 5%
Pd/C catalyst being prepared by drying a commercially available product
with 50% moisture content (5% Pd carbon powder with 50.0% moisture
content, E-type, pH 6.0, manufactured by N. E. Chemcat Corp.) at room
temperature for one day under a reduced pressure using a vacuum pump. The
temperature of the autoclave was raised with stirring the mixture under a
hydrogen pressure of 20 kg/cm.sup.2. Then the mixture was kept for 15
hours under a hydrogen pressure of 200 kg/cm.sup.2 with the heating
maintained at 190.degree. C. The hydroxyl value at the completion of the
reaction was 403.5 ›theoretical value: 480.23 (as an ether alcohol with an
average alkyl substituent number of 3.0)!. The reaction mixture was
dissolved in 200 ml of isopropanol, and the mixture was subjected to a
pressure-filtration through a membrane filter (PTFE, 0.2 .mu.m). The
filtrate was evaporated to give 551.34 g of a crude Compound (9b) (yield
of crude compound: 96.5%). The composition of the crude compound
determined by gas chromatography was as follows: 16% of dialkyl ether; 20%
of trialkyl ether; 51% of dialkyl ether monoketal; 10% of trialkyl ether
monoketal; and 1% of tetraalkyl ether. 500 g of the crude compound was
dissolved in 500 ml of hexane, which was washed three times with
methanol/water (200 ml/200 ml), three times with methanol/water (200
ml/100 ml), and four times with methanol/water (100 ml/100 ml). The upper
hexane layer obtained was evaporated to give 251.84 g of partially
purified hydrogenated compound.
The obtained compound was dissolved in 250 ml of hexane and purified by
silica gel column chromatography. The fractions eluted with hexane/ethanol
(99/1) were collected and evaporated to give 131.92 g of Compound (9b).
The obtained Compound (9b) has a purity of 97.7% as determined by gas
chromatography, and a hydroxyl value of 327.5 (theoretical value: 322.01).
IR (NEAT, cm.sup.-1): 3492 (O-H stretching), 2972, 2936, 2884 (C-H
stretching), 1468, 1378 (C-H deformation), 1082 (C-O stretching)
.sup.1 H NMR (CDCl.sub.3, .delta.ppm): 0.92 (9H, triplet, --CH.sub.2
CH.sub.3) 1.12 (6H, doublet, --CH.sub.2 CH.sub.3) 1.38 (3H, singlet,
(--O--).sub.2 C(CH.sub.3)CH.sub.2 CH.sub.3) 1.43-1.80 (6H, multiplet,
--CH.sub.2 CH.sub.3) 2.85 (2H, singlet, --OH) 3.29-4.33 (10H, multiplet,
--O--CH.sub.2 --, --O--CH--)
MASS (FD): 349 (M+1)
Example 1-10
Synthesis of 1,3,6-tri-O-(1-methylpropyl)sorbital ›Compound (10)!
251.84 g of the partially purified hydrogenated compound obtained in
Example 1-9 was dissolved in 250 ml of hexane and purified by silica gel
column chromatography. That is, after Compound (9b) was eluted with
hexane/ethanol (99/1), fractions eluted with hexane/ethanol (95/5) were
collected and evaporated to give 55.42 g of Compound (10). The obtained
compound had a purity of 97.3% as determined by gas chromatography and a
hydroxyl value of 453.1 (theoretical value of 480.24).
IR (NEAT, cm.sup.-1): 3464 (O-H stretching), 2972, 2932, 2880 (C-H
stretching), 1466, 1380 (C-H deformation), 1086 (C-O stretching)
.sup.1 H NMR (CDCl.sub.3, .delta.ppm): 0.92 (9H, triplet, --CH.sub.2
CH.sub.3) 1.13 (9H, doublet, --CHCH.sub.3) 1.32-1.78 (6H, multiplet,
--CH.sub.2 CH.sub.3) 3.13 (3H, broad singlet, --OH) 3.30-4.02
(--O--CH.sub.2 --, --O--CH--)
MASS(FD): 351 (M+1)
Example 1-11
Synthesis of
1,6-di-O-(1-methylpropyl)-di-O-methyl-O-(1-methylpropylidene)sorbitol
›Compound (11)!
In a 1-liter reaction vessel equipped with a thermometer, a reflux
condenser, a dropping funnel, and a stirrer, 12.38 g (0.516 mol) of sodium
hydride powder and 300 ml of toluene were placed. 70 g (0.201 mol) of
Compound (9b) obtained in Example 1-9 was dissolved in 100 ml of toluene,
and added dropwise to the vessel over 20 minutes with stirring at room
temperature under nitrogen atmosphere. The reaction mixture was heated to
110.degree. C. and refluxed with stirring for 30 minutes. After the
mixture was cooled to 50.degree. C., 65.08 g (0.516 mol) of dimethyl
sulfate was added dropwise over 1 hour with the temperature maintained at
50.degree. C. The mixture was matured for 1 hour at 80.degree. C. After
the mixture was cooled and 206.4 g of 10% aqueous solution (0.516 mol) of
sodium hydroxide was added, the mixture was stirred at 70.degree. to
80.degree. C. for 30 minutes. After being cooled to room temperature, the
mixture was extracted with 200 ml of ether, washed twice with 100 ml of
saturated brine, dried over anhydrous sodium sulfate, and evaporated to
give 76.72 g of viscous oily substance. The substance obtained was
subjected to a reduced-pressure distillation to give 68.83 g of Compound
(11) (yield: 92.1%). The obtained Compound (11) had a boiling point of
127.degree. to 128.degree. C. at 0.4 mmHg, a purity of 99.0% as determined
by gas chromatography, and a hydroxyl value of 0.67 (theoretical value:
0).
IR (NEAT, cm.sup.-1): 2974, 2925 (C-H deformation), 1470, 1377, 1341 (C-H
deformation), 1089 (C-O stretching)
.sup.1 H NMR (CDCl.sub.3, .delta.ppm): 0.90 (9H, triplet, --CH.sub.2
CH.sub.3) 1.10-1.20 (6H, multiplet, --CH(CH.sub.3 CH.sub.2 CH.sub.3)
1.29-1.42 (3H, multiplet, (--O--).sub.2 C(CH.sub.3)CH.sub.2 CH.sub.3)
1.42-1.80 (6H, multiplet, --CH.sub.2 CH.sub.3) 3.29-3.80 (14H, multiplet,
--CH.sub.2 --O--CH(CH.sub.3)CH.sub.2 CH.sub.3, CH--O--CH.sub.3)
Example 1-12
Synthesis of 2,4,5-tri-O-ethyl-1,3,6-tri-O-(1-methylpropyl)sorbitol
›Compound (12)!
In a 300-milliliter reaction vessel equipped with a thermometer, a reflux
condenser, a dropping funnel, and a stirrer, 3.70 g (0.154 mol) of sodium
hydride powder and 100 ml of toluene were placed. 12 g (0.0342 mol) of
Compound (10b) obtained in Example 1-10 was dissolved in 50 ml of toluene,
and added dropwise to the vessel over 20 minutes with stirring at room
temperature under nitrogen atmosphere. The reaction mixture was heated to
110.degree. C. and refluxed with stirring for 30 minutes with maintaining
the temperature. After the mixture was cooled to 50.degree. C., 23.75 g
(0.154 mol) of dimethyl sulfate was added dropwise over 45 minutes with
the temperature maintained at 50.degree. C. The mixture was matured for 2
hours at 80.degree. C. After the mixture was cooled and 61.6 g (0.154 mol)
of 10% aqueous solution of sodium hydroxide was added, the mixture was
stirred at 70.degree. to 80.degree. C. for 30 minutes. After the mixture
was cooled to room temperature, the lower layer was discarded, and the
upper toluene layer was washed twice with 50 ml of saturated brine, dried
over anhydrous sodium sulfate, and evaporated to give 14.8 g of viscous
oily substance. The substance obtained was subjected to a reduced-pressure
distillation to give 13.69 g of Compound (12) (yield: 92.0%). The obtained
Compound (12) had a boiling point of 145.degree. to 146.degree. C. at 0.5
mmHg, a purity of 96.2% as determined by gas chromatography, and a
hydroxyl value of 0.5 (theoretical value: 0).
IR (NEAT, cm.sup.-1): 2974, 2932, 2878 (C-H stretching), 1467, 1377,
1341(C-H deformation), 1110 (C-O stretching)
.sup.1 H NMR (CDCl.sub.3, .delta.ppm): 0.82-1.08 (9H, triplet,
--CH(CH.sub.3)CH.sub.2 CH.sub.3) 1.08-1.80 (24H, multiplet,
--CH(CH.sub.3)CH.sub.2 CH.sub.3, --OCH.sub.2 CH.sub.3) 3.21-4.00 (17H,
multiplet, --CH--O--CH.sub.2 --, --CH--OCH(CH.sub.3)--)
Example 1-13
Synthesis of
1,6-di-O-(1,3-dimethylbutyl)-O-(1,3-dimethylbutylidene)sorbitol ›Compound
(13b)!
1) 1.2:3.4:5.6-tri-O-(1,3-dimethylbutylidene)sorbitol: Compound (13a)
In a 3-liter reaction vessel equipped with a thermometer, a reflux
condenser, a Dean and Stark trap, a calcium chloride tube, and a stirrer,
363.76 g (1.997 mol) of D-sorbitol, 1200 g (11.981 mol) of methyl isobutyl
ketone, 18.99 g (0.0998 mol) of p-toluene sulfonic acid 1 hydrate, and 300
ml of hexane were placed and heated with stirring. A reaction was carried
out at a temperature of from 93.degree. to 98.degree. C. for 23 hours
while distilling off a predetermined amount of water. After being cooled
to 60.degree. C., the reaction mixture was neutralized by adding 21.16 g
(0.1996 mol) of sodium carbonate, and stirred at 60.degree. C. for 30
minutes. After 200 g of water was added to the mixture and stirred at
60.degree. C. for 30 minutes, the mixture was allowed to stand to separate
into two layers. After the lower layer was discarded, the remaining
mixture was washed with 200 g of saturated brine and evaporated to give
736.65 g of crude Compound (13a). The obtained crude Compound (13a) was
subjected to a reduced-pressure distillation and a forerun was discarded.
657.62 of the residue obtained was subjected to an adsorption treatment by
passing through 33 g (5% by weight to the residue) of activated clay on a
filter (PTFE, 0.2 .mu.m) by a pressure filtration. As a result, 637.44 g
of Compound (13a) was obtained (yield: 74.5%).
The purity of Compound (13a) as determined by gas chromatography was 96.1%,
and a hydroxyl value was 34.3 (theoretical value: 0).
2) 1,6-di-O-(1,3-dimethylbutyl)-O-(1,3-dimethylbutylidene)sorbitol:
Compound (13b)
In a 1-liter autoclave, 612 g (1.428 mol) of Compound (13a) obtained above,
and 12.24 g (2% by weight) of 5% Pd/C catalyst were placed, the 5% Pd/C
catalyst being prepared by drying a commercially available product with
50% moisture content (5% Pd carbon powder with 50.0% moisture content,
E-type, pH 6.0, manufactured by N. E. Chemcat Corp.) at room temperature
for one day under a reduced pressure using a vacuum pump. The temperature
of the autoclave was raised with stirring the mixture under a hydrogen
pressure of 20 kg/cm.sup.2. Then the mixture was kept for 10 hours under a
hydrogen pressure of 200 kg/cm.sup.2 at 190.degree. C. The hydroxyl value
at the completion of the reaction was 366.9 ›theoretical value: 387.25 (as
an ether alcohol with an average alkyl substituent number of 3.0)!. The
reaction mixture was dissolved in 200 ml of hexane, and the mixture was
subjected to a pressure-filtration through a membrane filter (PTFE, 0.2
.mu.m). The filtrate was evaporated to give 482.73 g of hydrogenated
CompOund (13b) (yield: 77.8%). The composition of the hydrogenated
compound determined by gas chromatography was as follows: 21% of dialkyl
ether; 20% of trialkyl ether; 37% of dialkyl ether monoketal; and 8% of
trialkyl ether monoketal. 360 g of the compound was purified by silica gel
column chromatography using a hexane/ethanol (vol/vol=97/3) developing
solvent to give 66.0 g of Compound (13b). The purity of the obtained
Compound (13b) as determined by gas chromatography was 98.3%, and the
hydroxyl value was 267 (theoretical value: 259).
IR (NEAT, cm.sup.-1): 3436 (O-H stretching), 2960, 2878 (C-H stretching),
1470, 1377 (C-H deformation), 1092 (C-O stretching)
.sup.1 H NMR (CDCl.sub.3, .delta.ppm): 0.80-1.09 (18H, multiplet,
--CH(CH.sub.3).sub.2) 0.80-1.30 (9H, multiplet, --OCH(Ch.sub.3)CH.sub.2
--, (--O--).sub.2 C(CH.sub.3)CH.sub.2 --) 1.30-1.65 (8H, multiplet,
--CH.sub.2 CH(CH.sub.3).sub.2) 1.65-1.82 (2H, multiplet,
--CH(CH.sub.3).sub.2) 2.36-2.82 (2H, broad singlet, --OH) 3.33-4.40 (10H,
multiplet, --CHOCH.sub.2 --, --CH--O--)
MASS (FD): 433 (M+1)
Example 1-14
Synthesis of 1,6-di-O-(1,3-dimethylbutyl)sorbitol ›Compound (14)!
The hydrogenated compound obtained in Example 1-13 was purified by further
carrying out silica gel column chromatography. That is, after Compound
(13b) was eluted with hexane/ethanol (vol/vol=97/3), Compound (14) was
eluted with a hexane/ethanol (vol/vol=95/5) developing solvent. As a
result, 57.9 g of Compound (14) was obtained. The purity of Compound (14)
was determined to be 83.7% by gas chromatography, and the hydroxyl value
of the compound was 614 (theoretical value: 641).
IR (NEAT, cm.sup.-1): 3436 (O-H stretching), 2962, 2873 (C-H stretching),
1470, 1377 (C-H deformation), 1089 (C-O stretching)
.sup.1 H NMR (CDCl.sub.3, .delta.ppm): 0.85-1.02 (12H, multiplet,
--CH(CH.sub.3).sub.3) 1.15 (6H, doublet, --OCH(CH.sub.3)--) 1.22-1.64 (4H,
multiplet, --CH.sub.2 CH(CH.sub.3).sub.2) 1.64-1.90 (2H, multiplet,
--CH(CH.sub.3).sub.2) 3.32 (4H, singlet, --OH) 3.45-4.02 (10H, multiplet,
--CHOCH.sub.2 --, --CH--O--)
MASS (FD): 351 (M+1)
Example 1-15
Synthesis of
1,6-di-O-(1,3-dimethylbutyl)-di-O-methyl-O-(1,3-dimethylbutylidene)sorbito
l ›Compound (15)!
In a 1-liter reaction vessel equipped with a thermometer, a reflux
condenser, a dropping funnel, and a stirrer, 15.6 g (0.39 mol) of sodium
hydride (content: 60%, oily) was placed. The sodium hydride was washed
with 100 ml of hexane by decantation. To the vessel, 200 ml of toluene was
added and stirred, to which 64.1 g (0.15 mol) of Compound (13b) obtained
in Example 1-13 dissolved in 100 ml of toluene was added dropwise over 15
minutes at room temperature. The mixture was further stirred for 1 hour at
100.degree. C. After the mixture was cooled to 40.degree. C., 49.1 g (0.39
mol) of dimethyl sulfate was added dropwise over 1 hour with the
temperature maintained below 60.degree. C. After the mixture was further
stirred for 1 hour at 60.degree. C. and cooled, 156 g of 10% aqueous
solution (0.39 mol) of sodium hydroxide was added and the mixture was
stirred at 70.degree. to 80.degree. C. for 1 hour. After cooling, the
mixture was allowed to phase separate. The water layer was extracted twice
with 150 ml of diethyl ether, and the organic layer was combined with
ether extracts. The mixture was washed three times with 100 ml of
saturated brine, dried over anhydrous sodium sulfate, and evaporated to
distill away the solvent to give 68.0 g of viscous oily substance. The
substance obtained was purified by silica gel column chromatography using
a hexane/diethyl ether ›95/5-90/10 (vol/vol)! developing solvent. As a
result, 56.6 g of Compound (15) was obtained, The purity determined by gas
chromatography was 97.7%.
IR (NEAT, cm.sup.-1): 2956, 2878 (C-H stretching), 1470, 1374 (C-H
deformation), 1125, 1095 (C-O stretching)
.sup.1 H NMR (CDCl.sub.3, .delta.ppm): 0.70-1.08 (18H, --CH.sub.2
CH(CH.sub.3).sub.2) 1.08-1.30 (9H, --OCH(CH.sub.3)CH.sub.2 --,
(--O--).sub.2 C(CH.sub.3)CH.sub.2 --) 1.30-1.67 (6H,
--OCH(CH.sub.3)CH.sub.2 --, (--O--).sub.2 C(CH.sub.3)CH.sub.2 --)
1.67-1.96 (3H, --CH(CH.sub.3).sub.2) 3.22-4.25 (16H, --O--CH.sub.2 --,
--O--CH--, --OCH.sub.3)
Example 1-16
Synthesis of a mixture of
2,3,4,5-tetra-O-methyl-1,6-di-O-(1,3-dimethylbutyl)sorbitol,
2,4,5-tri-O-methyl-1,3,6-tri-O-(1,3-dimethylbutyl)sorbitol,
1,6-di-O-(1,3-dimethylbutyl)-di-O-methyl-O-(1,3-dimethylbutylidene)sorbito
l,
O-methyl-1,3,6-tri-O-(1,3-dimethylbutyl)-O-(1,3-dimethylbutylidene)sorbito
l, 2,3,4,5,6-penta-O-methyl-1-O-(1,3-dimethylbutyl)sorbitol, and
di-O-methyl-1,3,6,x-tetra-O-(1,3-dimethylbutyl)sorbitol ›Compounds (16c)!
1) Ketals formed from sorbitol and methyl isobutyl ketone: Compounds (16a)
In a 3-liter reaction vessel equipped with a thermometer, a reflux
condenser, a Dean and Stark trap, a calcium chloride tube, and a stirrer,
363.76 g (1.997 mol) of D-sorbitol, 1200 g (11.981 mol) of methyl isobutyl
ketone, 18.99 g (0.0998 mol) of p-toluene sulfonic acid 1 hydrate, and 300
ml of hexane were placed and heated with stirring. A reaction was carried
out at a temperature of from 93.degree. to 95.degree. C. for 5 hours while
distilling off 60% of a predetermined amount of water. After being cooled
to 60.degree. C., the reaction mixture was neutralized by adding 21.16 g
(0.1996 mol) of sodium carbonate, and stirred at 60.degree. C. for 30
minutes. After 200 g of water was added to the mixture and stirred at
60.degree. C. for 30 minutes, the mixture was allowed to stand to separate
into two layers. After the lower layer was discarded, the remaining
mixture was washed with 200 g of saturated brine, and evaporated to give
544.6 g of crude Compounds (16a). The obtained crude Compounds (16a) was
subjected to a reduced-pressure distillation and a forerun was discarded.
486.2 of the residue obtained was subjected to an adsorption treatment by
passing through 24.31 g (5% by weight to the residue) of activated clay on
a filter (PTFE, 0.2 .mu.m) under pressure. As a result, 471.3 g of
Compounds (16a) was obtained (yield: 55.1%). The purity of Compounds (16a)
as determined by gas chromatography was 95% ›including both diketal and
triketal; diketal/triketal=33/67 (weight ratio)!.
2) Hydrogenated compounds of ketals formed from sorbitol and methyl
isobutyl ketone: Compounds (16b)
In a 1-liter autoclave, 450 g (1.120 mol) of Compounds (16a) obtained
above, which was sufficiently dehydrated, and 9.0 g (2% by weight) of 5%
Pd/C catalyst were placed, the 5% Pd/C catalyst being prepared by drying a
commercially available product with 50% moisture content (5% Pd carbon
powder with 50.0% moisture content, E-type, pH 6.0, manufactured by N. E.
Chemcat Corp.) at room temperature for one day under a reduced pressure
using a vacuum pump. The temperature of the autoclave was raised with
stirring the mixture under a hydrogen pressure of 20 kg/cm.sup.2. Then the
mixture was kept for 20 hours under a hydrogen pressure of 200 kg/cm.sup.2
at 190.degree. C. After the completion of the reaction, the mixture was
dissolved in 200 ml of hexane, and subjected to a pressure-filtration
through a membrane filter (PTFE, 0.2 .mu.m). Hexane in the filtrate was
distilled away to give 433 g of a crude Compounds (16b) (yield of the
crude compounds: 95%).
The purity of the compounds obtained was determined to be 90% by gas
chromatography (including dialkyl ether, trialkyl ether, dialkyl ether
monoketal, trialkyl ether monoketal, monoalkyl ether, and tetraalkyl
ether; weight ratio of the components: dialkyl ether:trialkyl
ether:dialkyl ether monoketal:trialkyl ether monoketal:monoalkyl
ether:tetraalkyl ether=63.5:16.0:14.7:2.9:2.7:0.2; hydroxyl value=444.5).
3) A mixture of
2,3,4,5-tetra-O-methyl-1,6-di-O-(1,3-dimethylbutyl)sorbitol, 2,4,5-tri-O-m
ethyl-1,3,6-tri-O-(1,3-dimethylbutyl)sorbitol,
1,6-di-O-(1,3-dimethylbutyl)-di-O-methyl-O-(1,3-dimethylbutylidene)sorbito
l,
1,6,x-tri-O-(1,3-dimethylbutyl)-O-methyl-O-(1,3-dimethylbutylidene)sorbito
l, 2,3,4,5,6-penta-O-methyl-1-O-(1,3-dimethylbutyl)sorbitol, and
di-O-methyl-1,3,6,x-tetra-O-(1,3-dimethylbutyl)sorbitol: Compounds (16c)
In a 2-liter reaction vessel equipped with a thermometer, a reflux
condenser, a dropping funnel, and a stirrer, 28.5 g (1.19 mol) of sodium
hydride powder and 900 ml of toluene were placed. 100 g (0.79 mol as
hydroxyl group) of Compounds (16b) obtained in 2) above was dissolved in
100 ml of toluene, and added dropwise to the vessel over 30 minutes with
stirring under nitrogen atmosphere. Then 50 ml of toluene was added to the
vessel. The reaction mixture was heated to 110.degree. C. and refluxed
with stirring for 1 hour at 110.degree. C. After the mixture was cooled to
50.degree. C., 149.9 g (1.19 mol) of dimethyl sulfate was added dropwise
over 1 hour with the temperature maintained at 50.degree. C. 300 ml of
toluene was added and the mixture was matured for 1 hour at 80.degree. C.
After the mixture was cooled and 476 g of 10% aqueous solution (1.19 mol)
of sodium hydroxide was added, the mixture was stirred at 70.degree. to
80.degree. C. for 30 minutes. The mixture was cooled to room temperature
and allowed to stand to phase separate. The lower layer was discarded. The
upper toluene layer was washed 4 times with saturated brine, dried over
anhydrous sodium sulfate, and evaporated to give 98.4 g of viscous oily
substance, Compounds (16c) (yield: 89%). The purity of the substance was
determined to be 90% by gas chromatography. The composition of the
substance was as follows: 56.8% by weight of
2,3,4,5-tetra-O-methyl-1,6-di-O-(1,3-dimethylbutyl)sorbitol, 14.3% by
weight of 2,4,5-tri-O-methyl-1,3,6-tri-O-(1,3-dimethylbutyl)sorbitol, 3.2%
by weight of
1,6-di-O-(1,3-dimethylbutyl)-di-O-methyl-O-(1,3-dimethylbutylidene)sorbito
l, 2.6% by weight of
1,3,6-tri-O-(1,3-dimethylbutyl)-O-methyl-O-(1,3-dimethylbutylidene)sorbito
l, 2.4% by weight of
2,3,4,5,6-penta-O-methyl-1-O-(1,3-dimethylbutyl)sorbitol, and 2% by weight
of di-O-methyl-1,3,6,x-tetra-O-(1,3-dimethylbutyl)sorbitol
IR (NEAT, cm.sup.-1): 2956, 2878, 2830 (C-H stretching), 1470, 1374,
1350(C-H deformation), 1110 (C-O stretching)
Example 2-1
With respect to each of the oils used in the present inventive products and
comparative products, kinematic viscosities at 40.degree. C. and
100.degree. C. were measured in accordance with JIS K-2283. The results
are shown in Tables 1 and 2.
TABLE 1
__________________________________________________________________________
No. of Oil Kinematic Viscosity
Fluidity
for Inventive (mm.sup.2 /s)
at Low
Product
Compound Structure 40.degree. C.
100.degree. C.
Temperature
__________________________________________________________________________
(6)
##STR19## 27.03 4.62 Fluid
(7)
##STR20## 56.61 7.20 Fluid
(8)
##STR21## 16.37 3.16 Fluid
(Ether alkyl groups, except for those at both ends, may be
arranged at
random or in block form.)
__________________________________________________________________________
Note: The parenthesized figures correspond to the numbers for oils in
Examples 11 to 116.
TABLE 2
__________________________________________________________________________
No. of Oil Kinematic
Fluidityy
for Inventive (mm.sup.2 /s)
at Low
Product Compound Structure 40.degree. C.
100.degree. C.
Temperature
__________________________________________________________________________
(11)
##STR22## 11.55 2.39 Fluid
(12)
##STR23## 11.73 2.61 Fluid
(M-1) (6) 67% by weight + (7) 33% by weight
35.29 5.37 Fluid
(8-1) Synthesized according to Example 1-8-1.
24.36 4.20 Fluid
(8-2) Synthesized according to Example 1-8-2.
45.41 6.22 Fluid
(16c) Synthesized according to Example 1-16.
11.94 2.62 Fluid
Oil (1) for
Naphthene oil 30.0 4.4 Fluid
Comparative Product
__________________________________________________________________________
Example 2-2
With respect to each of the oils used in the present inventive products and
comparative products, fluidity at low temperatures was measured.
Specifically, oil samples used in Example 2-1 were placed in a constant
temperature vessel maintained at -20.degree. C. for 1 hour, and observed
whether or not the samples showed fluidity. The results are shown in
Tables 1 and 2.
Example 2-3
Each of inventive products and comparative products was prepared, each
being a composition consisting of 1,1,1,2-tetrafluoroethane (HFC134a) and
one of the oils for inventive and comparative products listed in Tables 3
and 4, and the compatibility between the hydrofluorocarbon and the oil was
evaluated. Specifically, the two-phase separation temperature for
1,1,1,2-tetrafluoroethane at low temperatures was measured at sample oil
concentrations of 10 vol %, 20 vol %, 30 vol %, and 40 vol %. The results
are shown in Tables 3 and 4.
As is evident from Tables 3 and 4, the oils used in the inventive products
had a better compatibility with HFC134a than those used in the comparative
products.
TABLE 3
__________________________________________________________________________
Separation Temperature
No. of Oil at Low Temperature
(.degree.C.)
for Inventive 10
Product
Compound Structure vol %
20 vol %
30 vol
40 vol
__________________________________________________________________________
%
(6)
##STR24## -56 -52 -51 -52
(15)
##STR25## -48 -39 -34 -39
(Ether alkyl groups, except for those at both ends, may be arranged
at
random or in block form.)
(11)
##STR26## <-70
<-70 <-70 <-70
(Ether alkyl groups, except for those at both ends, may be arranged
at
random or in block form.)
__________________________________________________________________________
TABLE 4
__________________________________________________________________________
No. of Oil Separation Temperature
for at Low Temperature
(.degree.C.)
Inventive 10 20 30 40
Product
Compound Structure vol %
vol %
vol
vol
__________________________________________________________________________
%
(12)
##STR27## <-70
<-70
-69 <-70
M-1
##STR28## -18
-12
-16 -26
(16c) Synthesized according to Example 1-16 <-70
<-70
<-70
<-70
Oil (1) for
Naphthene oil >20 >20 >20 >20
Comparative
Product
__________________________________________________________________________
Example 2-4
Each of the present inventive products was tested for the thermal stability
by a sealed tube test.
Specifically, 10 g of an oil with a moisture content adjusted below 20 ppm
and 5 g of HFC134a were placed in a glass tube. After iron, copper, and
aluminum were added thereto as catalysts, the glass tube was sealed. After
tested at 175.degree. C. for 14 days and 28 days, the composition of oil
and HFC134a was observed for its appearance and presence of precipitation.
After HFC134a was removed, the acid value of oil was measured. The results
are shown in Tables 5 and 6.
As is evident from Tables 5 and 6, the thermal stability of the inventive
products was good, all of the inventive products showing no abnormality in
appearance, and no precipitation.
TABLE 5
__________________________________________________________________________
No. of Acid Value
Oil for (mgKOH/g)
Inventive Test Precipi-
Before
After
Product
Compound Structure Period
Appearance
tation
Test Test
__________________________________________________________________________
(11)
##STR29##
##STR30##
##STR31##
##STR32##
##STR33##
##STR34##
(Ether alkyl groups, except for those at both ends, may be arranged
at
random or in block form.)
(12)
##STR35##
##STR36##
##STR37##
##STR38##
##STR39##
##STR40##
__________________________________________________________________________
TABLE 6
__________________________________________________________________________
No. of Acid Value
Oil for (mgKOH/g)
Inventive Test Precipi-
Before
After
Product
Compound Structure
Period
Appearance
tation
Test
Test
__________________________________________________________________________
(8-2)
Synthesized according to Example 1-8-2.
14 days
Normal
None
<0.05
<0.05
28 days
Normal
None
<0.05
<0.05
(16c)
Synthesized according to Example 1-16.
14 days
Normal
None
<0.05
<0.05
28 days
Normal
None
<0.05
<0.05
__________________________________________________________________________
Example 2-5
Each of the present inventive products and a comparative product were
tested for the hydrolysis resistance by a sealed tube test.
Specifically, 10 g of an oil with a moisture content adjusted at 3000 ppm,
and 5 g of HFC134a were placed in a glass tube. After iron, copper, and
aluminum were added thereto as catalysts, the glass tube was sealed. After
tested at 175.degree. C. for 14 days, the composition of oil and HFC134a
was observed for its appearance and presence of precipitation. After the
hydrofluorocarbon was removed, the acid value of oil was measured. The
results are shown in Tables 7 and 8. As is evident from Tables 7 and 8,
the hydrolysis resistance of the inventive products was good, with showing
no abnormality in appearance, no precipitation, and, unlike the
comparative product using an ester, no increase in the acid value.
TABLE 7
__________________________________________________________________________
Sealed Tube Test
No. of Acid Value
Oil for (mgKOH/g)
Inventive Precipi-
Before
After
Product
Compound Structure Appearance
tation
Test
Test
__________________________________________________________________________
(11)
##STR41## Normal
None
<0.05
<0.05
(Ether alkyl groups, except for those at both ends, may be arranged
at random or in block form.)
(12)
##STR42## Normal
None
<0.05
<0.05
__________________________________________________________________________
TABLE 8
__________________________________________________________________________
Sealed Tube Test
No. of Acid Value
Oil for (mgKOH/g)
Inventive Precipi-
Before
After
Product Compound Structure
Appearance
tation
Test
Test
__________________________________________________________________________
(8-2) Synthesized according to Example 1-8-2.
Normal
None
<0.05
<0.05
(16c) Synthesized according to Example 1-16.
Normal
None
<0.05
<0.05
Oil (2) for
Trimethylolpropane tricaproate.
Normal
None
0.05
7.3
Comparative Product
__________________________________________________________________________
Example 2-6
With respect to each of the oils used in the present inventive products and
comparative products, volume resistivity at 25.degree. C. was measured in
accordance with JIS C-2101. The results are shown in Tables 9 and 10.
As is evident from Tables 9 and 10, the oils used in the inventive products
had better volume resistivity than those used in the comparative products.
TABLE 9
__________________________________________________________________________
No. of Oil Volume
for Inventive Resistivity
Product
Compound Structure (.OMEGA..multidot. cm)
__________________________________________________________________________
(15)
##STR43## 2.0 .times. 10.sup.14
(Ether alkyl groups, except for those at both ends, may be arranged
at random or in block form.)
(11)
##STR44## 2.1 .times. 10.sup.12
(12)
##STR45## 2.0 .times. 10.sup.13
__________________________________________________________________________
TABLE 10
__________________________________________________________________________
No. of Oil Volume
for Inventive Resistivity
Product
Compound Structure (.OMEGA. .multidot. cm)
__________________________________________________________________________
(8-2) Synthesized according to Example 1-8-2.
9.9 .times. 10.sup.13
(16c) Synthesized according to Example 1-16.
9.4 .times. 10.sup.13
##STR46##
##STR47## 2.0 .times. 10.sup.11
Oil (4) for
Unirube MB-11 (MW1000) 5.0 .times. 10.sup.9
Comparative
(Polyoxypropylene glycol monobutyl ether)
Product
Oil (5) for
Propyleneoxide-1,2-epoxybutane copolymer with methyl ethers at both
ends .sup. 1.3 .times. 10.sup.10
Comparative
(MW1245)
Product
__________________________________________________________________________
Example 2-7
Each of the present inventive products, each comprising a hydrofluorocarbon
and a refrigeration oil containing an ether compound used in the present
invention and additives, was tested for the thermal stability, etc. by a
sealed tube test.
Specifically, 10 g of an oil with a moisture content adjusted at 3000 ppm
and 5 g of HFC134a were placed in a glass tube. After iron, copper, and
aluminum were added thereto as catalysts, the glass tube was sealed. After
tested at 175.degree. C. for 14 days, the composition of oil and HFC134a
was observed for its appearance and presence of precipitation. After
HFC134a was removed, the moisture content of the oil was measured. The
results are shown in Table 11. As is evident from Table 11, the thermal
stability of the inventive products was good, with all of the inventive
products showing no abnormality in appearance, and no precipitation. Also,
a good dehydration could be achieved.
While the invention has been described in detail and with reference to
specific embodiments thereof, it will be apparent to one skilled in the
art that various changes and modifications can be made therein without
departing from the spirit and scope thereof.
TABLE 11
__________________________________________________________________________
Water Content
(ppm)
Inventive Additives Precipi-
Before
After
Product
Ether Used in the Present Invention
(Amount*.sup.1) Appearance
tation
Test
Test
__________________________________________________________________________
A-1 (8-2) 1,3-dicyclohexylcarbbdiimide
(3)
Normal
None
3000
212
Synthesized according to Example 1-8-2.
A-2 (15) 1,3-dicyclohexylcarbodiimide
(3)
Normal
None
3000
198
A-3 (6) 1,1-bis(2-methylpropoxy)-
(3)
Normal
None
3000
154
cyclohexane
A-4 (6) Glycidyl 2-ethylhexanoate
(3)
Normal
None
3000
645
A-5 (12) 3,4-epoxycyclohexylmethyl
(3)
Normal
None
3000
312
3,4-epoxycyclohexanecarboxylate
__________________________________________________________________________
*.sup.1 Parts by weight based on 100 parts by weight of the ether used in
the present invention.
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